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+# Remove Cover Page Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** Remove the cover page from the teaching-book data model, stored JSON, and workspace UI.
+
+**Architecture:** First make the domain model lesson-only, then add server-side normalization so old book JSON loses `cover` and invalid `selectedId` values. Finally update the Vue store and components so users can only select and edit lesson pages.
+
+**Tech Stack:** Vue 3, Vitest, Vue Test Utils, Bun, bun:sqlite, Hono, TypeScript.
+
+---
+
+## File Structure
+
+- Modify `src/domain/teachingDesign.ts`: remove `BookCover`, remove `cover`, and change `selectedId` to `DesignId | null`.
+- Modify `src/domain/teachingDesign.test.ts`: update defaults and type assertions.
+- Modify `server/db.ts`: normalize stored book JSON on `openDb()` and before saving.
+- Modify `server/db.test.ts`: cover migration of legacy `cover`, legacy `'cover'` selection, invalid selected ids, and route-safe persistence.
+- Modify `server/routes/books.test.ts`: update save/get expectations so `cover` is not persisted.
+- Modify `src/composables/useTeachingBook.ts`: remove `updateCover`, use `null` selection, and update import/delete/clear behavior.
+- Modify `src/composables/useTeachingBook.test.ts`: update tests away from cover and add null-selection coverage.
+- Modify `src/components/LessonSidebar.vue`: remove cover props/events/UI.
+- Modify `src/components/LessonSidebar.test.ts`: assert no cover button and keep drag/drop coverage.
+- Modify `src/components/A4Workspace.vue`: remove cover props/events/import and render only selected lessons.
+- Create `src/components/A4Workspace.test.ts`: assert no cover page is rendered.
+- Modify `src/components/WorkspaceView.vue`: stop passing cover/update-cover.
+- Modify `src/components/WorkspaceView.test.ts`: assert the loaded workspace does not show a cover entry.
+- Delete `src/components/CoverPage.vue`.
+- Modify `src/style.css`: remove cover-specific CSS.
+
+### Task 1: Domain Model
+
+**Files:**
+- Modify: `src/domain/teachingDesign.test.ts`
+- Modify: `src/domain/teachingDesign.ts`
+
+- [ ] **Step 1: Write failing domain tests**
+
+In `src/domain/teachingDesign.test.ts`, replace the `createEmptyBook` describe block with:
+
+```ts
+describe('createEmptyBook', () => {
+  it('creates the schema defaults with no selected page and an ISO timestamp', () => {
+    const book = createEmptyBook()
+
+    expect(book.schemaVersion).toBe(BOOK_SCHEMA_VERSION)
+    expect(book.selectedId).toBeNull()
+    expect(book).not.toHaveProperty('cover')
+    expect(new Date(book.updatedAt).toISOString()).toBe(book.updatedAt)
+  })
+
+  it('creates independent design collections', () => {
+    const first = createEmptyBook()
+    const second = createEmptyBook()
+
+    first.designs.push(createEmptyTeachingDesign('1.md'))
+
+    expect(first.designs).not.toBe(second.designs)
+    expect(second.designs).toEqual([])
+  })
+})
+```
+
+In the `domain types` test, replace the selected id assertion with:
+
+```ts
+    expectTypeOf<TeachingBook['selectedId']>().toEqualTypeOf<DesignId | null>()
+```
+
+- [ ] **Step 2: Run domain tests to verify failure**
+
+Run:
+
+```bash
+rtk npm run test -- src/domain/teachingDesign.test.ts
+```
+
+Expected: FAIL because `createEmptyBook()` still returns `cover` and `selectedId: 'cover'`.
+
+- [ ] **Step 3: Update domain model**
+
+In `src/domain/teachingDesign.ts`, delete:
+
+```ts
+export interface BookCover {
+  courseName: string
+  teacherName: string
+}
+```
+
+Replace `TeachingBook` with:
+
+```ts
+export interface TeachingBook {
+  schemaVersion: typeof BOOK_SCHEMA_VERSION
+  designs: TeachingDesign[]
+  selectedId: DesignId | null
+  updatedAt: string
+}
+```
+
+Replace `createEmptyBook()` with:
+
+```ts
+export function createEmptyBook(): TeachingBook {
+  return {
+    schemaVersion: BOOK_SCHEMA_VERSION,
+    designs: [],
+    selectedId: null,
+    updatedAt: new Date().toISOString(),
+  }
+}
+```
+
+- [ ] **Step 4: Run domain tests to verify pass**
+
+Run:
+
+```bash
+rtk npm run test -- src/domain/teachingDesign.test.ts
+```
+
+Expected: PASS.
+
+### Task 2: Server Data Normalization
+
+**Files:**
+- Modify: `server/db.test.ts`
+- Modify: `server/routes/books.test.ts`
+- Modify: `server/db.ts`
+
+- [ ] **Step 1: Write failing DB migration tests**
+
+In `server/db.test.ts`, add these imports:
+
+```ts
+import { existsSync, rmSync } from 'node:fs'
+import { join } from 'node:path'
+import { tmpdir } from 'node:os'
+```
+
+Add this helper above `describe('db', () => {`:
+
+```ts
+function tempDbPath(name: string): string {
+  const path = join(tmpdir(), `fake-teaching-design-${name}-${crypto.randomUUID()}.db`)
+  if (existsSync(path)) rmSync(path)
+  return path
+}
+```
+
+Append these tests inside `describe('db', () => { ... })`:
+
+```ts
+  it('migrates legacy cover data and cover selection on open', () => {
+    const path = tempDbPath('cover-migration')
+    const db = openDb(path)
+    const design = createEmptyTeachingDesign('1.md')
+    const legacy = {
+      schemaVersion: 1,
+      cover: { courseName: '旧课程', teacherName: '旧教师' },
+      designs: [design],
+      selectedId: 'cover',
+      updatedAt: '2026-01-01T00:00:00.000Z',
+    }
+    db.run('INSERT INTO books (id, name, data, created_at, updated_at) VALUES (?, ?, ?, ?, ?)', [
+      'legacy-1',
+      '旧整本',
+      JSON.stringify(legacy),
+      '2026-01-01T00:00:00.000Z',
+      '2026-01-01T00:00:00.000Z',
+    ])
+    db.close()
+
+    const reopened = openDb(path)
+    const migrated = getBook(reopened, 'legacy-1')!.data
+    const raw = reopened.query<{ data: string }, [string]>('SELECT data FROM books WHERE id = ?').get('legacy-1')!.data
+    reopened.close()
+    rmSync(path)
+
+    expect(migrated).not.toHaveProperty('cover')
+    expect(migrated.selectedId).toBe(design.id)
+    expect(JSON.parse(raw)).not.toHaveProperty('cover')
+  })
+
+  it('migrates legacy cover selection to null when no lessons exist', () => {
+    const path = tempDbPath('empty-cover-migration')
+    const db = openDb(path)
+    db.run('INSERT INTO books (id, name, data, created_at, updated_at) VALUES (?, ?, ?, ?, ?)', [
+      'legacy-empty',
+      '空整本',
+      JSON.stringify({
+        schemaVersion: 1,
+        cover: { courseName: '旧课程', teacherName: '旧教师' },
+        designs: [],
+        selectedId: 'cover',
+        updatedAt: '2026-01-01T00:00:00.000Z',
+      }),
+      '2026-01-01T00:00:00.000Z',
+      '2026-01-01T00:00:00.000Z',
+    ])
+    db.close()
+
+    const reopened = openDb(path)
+    const migrated = getBook(reopened, 'legacy-empty')!.data
+    reopened.close()
+    rmSync(path)
+
+    expect(migrated).not.toHaveProperty('cover')
+    expect(migrated.selectedId).toBeNull()
+  })
+
+  it('normalizes invalid selected ids to the first lesson', () => {
+    const db = openDb(':memory:')
+    const created = createBook(db, '示例整本')
+    const data = createEmptyBook()
+    const design = createEmptyTeachingDesign('1.md')
+    data.designs.push(design)
+    db.run('UPDATE books SET data = ? WHERE id = ?', [
+      JSON.stringify({ ...data, selectedId: 'missing-id' }),
+      created.id,
+    ])
+
+    expect(getBook(db, created.id)?.data.selectedId).toBe(design.id)
+  })
+```
+
+Update the existing `saves book data and updates updated_at` test to stop writing `data.cover` and assert `cover` is absent:
+
+```ts
+  it('saves book data and updates updated_at', () => {
+    const db = openDb(':memory:')
+    const created = createBook(db, '示例整本')
+    const data = createEmptyBook()
+    data.designs.push(createEmptyTeachingDesign('1.md'))
+
+    setSystemTime(new Date('2026-02-01T00:00:00.000Z'))
+    const result = saveBookData(db, created.id, data)
+
+    expect(result).toEqual({ id: created.id, name: '示例整本', updatedAt: '2026-02-01T00:00:00.000Z' })
+    expect(getBook(db, created.id)?.data).not.toHaveProperty('cover')
+  })
+```
+
+- [ ] **Step 2: Update route test expectations**
+
+In `server/routes/books.test.ts`, replace the `saves book data` test body with:
+
+```ts
+  it('saves book data without cover state', async () => {
+    const created = await createViaApi('示例整本')
+
+    const data = createEmptyBook()
+    data.designs.push(createEmptyTeachingDesign('1.md'))
+
+    const res = await app.request(`/api/books/${created.id}`, {
+      method: 'PUT',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ data: { ...data, cover: { courseName: '旧课程', teacherName: '旧教师' } } }),
+    })
+    expect(res.status).toBe(200)
+
+    const fetched = await app.request(`/api/books/${created.id}`)
+    const body = (await fetched.json()) as { data: Record<string, unknown> }
+    expect(body.data).not.toHaveProperty('cover')
+  })
+```
+
+Also update the import in `server/routes/books.test.ts`:
+
+```ts
+import { createEmptyBook, createEmptyTeachingDesign } from '../../src/domain/teachingDesign'
+```
+
+- [ ] **Step 3: Run DB and books route tests to verify failure**
+
+Run:
+
+```bash
+rtk bun test server/db.test.ts server/routes/books.test.ts
+```
+
+Expected: FAIL because stored JSON still preserves `cover` and `'cover'` selected ids.
+
+- [ ] **Step 4: Implement book normalization**
+
+In `server/db.ts`, add these internal types after `interface BookRow`:
+
+```ts
+type StoredTeachingBook = Omit<TeachingBook, 'selectedId'> & {
+  cover?: unknown
+  selectedId?: string | null
+}
+
+interface NormalizedBookData {
+  data: TeachingBook
+  changed: boolean
+}
+```
+
+Add this helper before `openDb()`:
+
+```ts
+function normalizeBookData(raw: StoredTeachingBook): NormalizedBookData {
+  const data = { ...raw, designs: Array.isArray(raw.designs) ? raw.designs : [] } as StoredTeachingBook
+  let changed = false
+
+  if ('cover' in data) {
+    delete data.cover
+    changed = true
+  }
+
+  const selectedId = data.selectedId ?? null
+  const firstDesignId = data.designs[0]?.id ?? null
+  const selectedExists =
+    selectedId !== null && data.designs.some((design) => design.id === selectedId)
+
+  let normalizedSelectedId: TeachingBook['selectedId']
+  if (selectedId === 'cover' || (selectedId !== null && !selectedExists)) {
+    normalizedSelectedId = firstDesignId
+    if (selectedId !== normalizedSelectedId) changed = true
+  } else {
+    normalizedSelectedId = selectedId as TeachingBook['selectedId']
+  }
+
+  return {
+    data: {
+      schemaVersion: data.schemaVersion,
+      designs: data.designs,
+      selectedId: normalizedSelectedId,
+      updatedAt: data.updatedAt,
+    },
+    changed,
+  }
+}
+
+function migrateStoredBooks(db: Database): void {
+  const rows = db.query<{ id: string; data: string }, []>('SELECT id, data FROM books').all()
+  for (const row of rows) {
+    const normalized = normalizeBookData(JSON.parse(row.data) as StoredTeachingBook)
+    if (normalized.changed) {
+      db.run('UPDATE books SET data = ? WHERE id = ?', [JSON.stringify(normalized.data), row.id])
+    }
+  }
+}
+
+function parseBookData(data: string): TeachingBook {
+  return normalizeBookData(JSON.parse(data) as StoredTeachingBook).data
+}
+```
+
+Update `openDb()` to run migration:
+
+```ts
+export function openDb(path: string): Database {
+  const db = new Database(path)
+  db.run('PRAGMA foreign_keys = ON')
+  db.run(SCHEMA)
+  migrateStoredBooks(db)
+  return db
+}
+```
+
+Replace all direct `JSON.parse(row.data) as TeachingBook` uses in `listBooks()` and `getBook()` with `parseBookData(row.data)`.
+
+In `saveBookData()`, normalize before storing:
+
+```ts
+  const normalized = normalizeBookData(data as StoredTeachingBook).data
+  db.run('UPDATE books SET data = ?, updated_at = ? WHERE id = ?', [JSON.stringify(normalized), now, id])
+```
+
+- [ ] **Step 5: Run DB and books route tests to verify pass**
+
+Run:
+
+```bash
+rtk bun test server/db.test.ts server/routes/books.test.ts
+```
+
+Expected: PASS.
+
+### Task 3: Store Selection Without Cover
+
+**Files:**
+- Modify: `src/composables/useTeachingBook.test.ts`
+- Modify: `src/composables/useTeachingBook.ts`
+
+- [ ] **Step 1: Write failing store tests**
+
+In `src/composables/useTeachingBook.test.ts`:
+
+Replace the `loads the book from the API` test with:
+
+```ts
+  it('loads the book from the API without cover state', async () => {
+    const data = createEmptyBook()
+    mockGetBook(data)
+
+    const store = useTeachingBook('b1')
+    await flushPromises()
+
+    expect(booksApi.getBook).toHaveBeenCalledWith('b1')
+    expect(store.loadStatus.value).toBe('loaded')
+    expect(store.book.value).not.toHaveProperty('cover')
+  })
+```
+
+Replace autosave test mutation:
+
+```ts
+    const design = createEmptyTeachingDesign('1.md')
+    store.book.value.designs.push(design)
+    store.updateDesign(design.id, (target) => {
+      target.topic = '新课程名'
+    })
+```
+
+Replace the save-error test mutation with the same `updateDesign()` pattern.
+
+Replace the clear test with:
+
+```ts
+  it('clearBook empties designs and clears selection', async () => {
+    const data = createEmptyBook()
+    data.designs.push(createEmptyTeachingDesign('1.md'))
+    data.selectedId = data.designs[0]!.id
+    mockGetBook(data)
+
+    const store = useTeachingBook('b1')
+    await flushPromises()
+
+    store.clearBook()
+
+    expect(store.book.value.designs).toEqual([])
+    expect(store.book.value.selectedId).toBeNull()
+  })
+```
+
+Add this test inside the describe block:
+
+```ts
+  it('selects null after removing the last selected lesson', async () => {
+    const data = createEmptyBook()
+    const design = createEmptyTeachingDesign('1.md')
+    data.designs.push(design)
+    data.selectedId = design.id
+    mockGetBook(data)
+
+    const store = useTeachingBook('b1')
+    await flushPromises()
+
+    store.removeDesign(design.id)
+
+    expect(store.book.value.designs).toEqual([])
+    expect(store.book.value.selectedId).toBeNull()
+    expect(store.selectedDesign.value).toBeNull()
+  })
+```
+
+- [ ] **Step 2: Run store tests to verify failure**
+
+Run:
+
+```bash
+rtk npm run test -- src/composables/useTeachingBook.test.ts
+```
+
+Expected: FAIL because `updateCover` still exists, `clearBook()` selects `'cover'`, and types still mention cover.
+
+- [ ] **Step 3: Update useTeachingBook types and behavior**
+
+In `src/composables/useTeachingBook.ts`:
+
+Remove `type BookCover` from imports.
+
+Change `TeachingBookStore` methods:
+
+```ts
+  selectPage: (id: DesignId) => void
+  moveDesign: (from: number, to: number) => void
+  removeDesign: (id: DesignId) => void
+  updateDesign: (id: DesignId, updater: (design: TeachingDesign) => void) => void
+```
+
+Delete `updateCover` from the interface and returned object.
+
+Replace `syncDerived()` selected-design logic with:
+
+```ts
+    selectedDesign.value = current.selectedId === null
+      ? null
+      : current.designs.find((design) => design.id === current.selectedId) ?? null
+```
+
+Replace the import selection block with:
+
+```ts
+    if (imported > 0 && book.value.selectedId === null && book.value.designs.length > 0) {
+      book.value.selectedId = book.value.designs[0]!.id
+    }
+```
+
+Change `selectPage()` signature:
+
+```ts
+  function selectPage(id: DesignId): void {
+    book.value.selectedId = id
+  }
+```
+
+In `removeDesign()`, replace fallback selection with:
+
+```ts
+      book.value.selectedId = designs[index]?.id ?? designs[index - 1]?.id ?? null
+```
+
+Delete `updateCover()`.
+
+In `clearBook()`, set:
+
+```ts
+    book.value.selectedId = null
+```
+
+- [ ] **Step 4: Run store tests to verify pass**
+
+Run:
+
+```bash
+rtk npm run test -- src/composables/useTeachingBook.test.ts
+```
+
+Expected: PASS.
+
+### Task 4: Components Without Cover
+
+**Files:**
+- Modify: `src/components/LessonSidebar.test.ts`
+- Create: `src/components/A4Workspace.test.ts`
+- Modify: `src/components/WorkspaceView.test.ts`
+- Modify: `src/components/LessonSidebar.vue`
+- Modify: `src/components/A4Workspace.vue`
+- Modify: `src/components/WorkspaceView.vue`
+- Delete: `src/components/CoverPage.vue`
+- Modify: `src/style.css`
+
+- [ ] **Step 1: Write failing component tests**
+
+In `src/components/LessonSidebar.test.ts`, use `selectedId: designs[0]?.id ?? null` in the existing mount. Add:
+
+```ts
+  it('does not render a cover navigation item', () => {
+    const designs = [createEmptyTeachingDesign('1.md')]
+    const wrapper = mount(LessonSidebar, {
+      props: { designs, selectedId: designs[0]?.id ?? null },
+    })
+
+    expect(wrapper.text()).not.toContain('封面')
+  })
+```
+
+Create `src/components/A4Workspace.test.ts`:
+
+```ts
+import { mount } from '@vue/test-utils'
+import { describe, expect, it } from 'vitest'
+import { createEmptyTeachingDesign } from '../domain/teachingDesign'
+import A4Workspace from './A4Workspace.vue'
+import TeachingDesignPage from './TeachingDesignPage.vue'
+
+describe('A4Workspace', () => {
+  it('renders the selected lesson without a cover page', () => {
+    const design = createEmptyTeachingDesign('1.md')
+    design.topic = '第一课'
+
+    const wrapper = mount(A4Workspace, {
+      props: { selectedDesign: design },
+    })
+
+    expect(wrapper.find('.cover-page').exists()).toBe(false)
+    expect(wrapper.findComponent(TeachingDesignPage).exists()).toBe(true)
+    expect(wrapper.text()).toContain('第一课')
+  })
+
+  it('renders no page when no lesson is selected', () => {
+    const wrapper = mount(A4Workspace, {
+      props: { selectedDesign: null },
+    })
+
+    expect(wrapper.find('.page').exists()).toBe(false)
+  })
+})
+```
+
+In `src/components/WorkspaceView.test.ts`, add this test:
+
+```ts
+  it('does not render a cover entry when lessons exist', async () => {
+    const data = createEmptyBook()
+    data.designs.push(createEmptyTeachingDesign('1.md'))
+    data.selectedId = data.designs[0]!.id
+    mockBook(data)
+
+    const wrapper = mount(WorkspaceView, { props: { bookId: 'b1' } })
+    await flushPromises()
+
+    expect(wrapper.text()).not.toContain('封面')
+  })
+```
+
+- [ ] **Step 2: Run component tests to verify failure**
+
+Run:
+
+```bash
+rtk npm run test -- src/components/LessonSidebar.test.ts src/components/A4Workspace.test.ts src/components/WorkspaceView.test.ts
+```
+
+Expected: FAIL because `LessonSidebar` still renders cover and `A4Workspace` still requires cover props/imports `CoverPage`.
+
+- [ ] **Step 3: Update LessonSidebar**
+
+In `src/components/LessonSidebar.vue`:
+
+Change props:
+
+```ts
+defineProps<{
+  designs: TeachingDesign[]
+  selectedId: DesignId | null
+}>()
+```
+
+Change emits:
+
+```ts
+const emit = defineEmits<{
+  select: [id: DesignId]
+  remove: [id: DesignId]
+  move: [from: number, to: number]
+}>()
+```
+
+Delete the `<button class="lesson-sidebar-item lesson-sidebar-cover">...</button>` block.
+
+- [ ] **Step 4: Update A4Workspace**
+
+Replace `src/components/A4Workspace.vue` with:
+
+```vue
+<script setup lang="ts">
+import type { TeachingDesign } from '../domain/teachingDesign'
+import TeachingDesignPage from './TeachingDesignPage.vue'
+
+defineProps<{
+  selectedDesign: TeachingDesign | null
+}>()
+
+const emit = defineEmits<{
+  'update:design': [design: TeachingDesign]
+}>()
+</script>
+
+<template>
+  <div class="a4-workspace">
+    <div class="a4-paper">
+      <TeachingDesignPage
+        v-if="selectedDesign"
+        :design="selectedDesign"
+        :editable="true"
+        @update:design="emit('update:design', $event)"
+      />
+    </div>
+  </div>
+</template>
+```
+
+- [ ] **Step 5: Update WorkspaceView**
+
+In `src/components/WorkspaceView.vue`:
+
+Remove `updateCover` from the `useTeachingBook()` destructuring.
+
+Replace the `A4Workspace` usage with:
+
+```vue
+          <A4Workspace
+            :selected-design="selectedDesign"
+            @update:design="handleDesignUpdate"
+          />
+```
+
+- [ ] **Step 6: Delete cover component and CSS**
+
+Delete `src/components/CoverPage.vue`.
+
+In `src/style.css`, delete the whole section from:
+
+```css
+/* Cover page */
+```
+
+through the `.cover-field-value` rule.
+
+Also delete `.lesson-sidebar-cover` rules because no element uses that class anymore.
+
+- [ ] **Step 7: Run component tests to verify pass**
+
+Run:
+
+```bash
+rtk npm run test -- src/components/LessonSidebar.test.ts src/components/A4Workspace.test.ts src/components/WorkspaceView.test.ts
+```
+
+Expected: PASS.
+
+### Task 5: Cleanup References and Verify
+
+- [ ] **Step 1: Search for remaining cover references**
+
+Run:
+
+```bash
+rtk rg -n "CoverPage|BookCover|cover|selectedId: 'cover'|'cover'|封面|lesson-sidebar-cover|cover-page" src server
+```
+
+Expected: Output contains only migration compatibility references in `server/db.ts`, `server/db.test.ts`, and `server/routes/books.test.ts`. It must not contain `src/components/CoverPage.vue`, `BookCover`, UI text `封面`, `lesson-sidebar-cover`, or `.cover-page`.
+
+- [ ] **Step 2: Run full frontend tests**
+
+Run:
+
+```bash
+rtk npm run test
+```
+
+Expected: PASS.
+
+- [ ] **Step 3: Run backend tests**
+
+Run:
+
+```bash
+rtk npm run test:server
+```
+
+Expected: PASS.
+
+- [ ] **Step 4: Run production build**
+
+Run:
+
+```bash
+rtk npm run build
+```
+
+Expected: PASS.
+
+- [ ] **Step 5: Review diff**
+
+Run:
+
+```bash
+rtk git diff -- src/domain/teachingDesign.ts src/domain/teachingDesign.test.ts server/db.ts server/db.test.ts server/routes/books.test.ts src/composables/useTeachingBook.ts src/composables/useTeachingBook.test.ts src/components/LessonSidebar.vue src/components/LessonSidebar.test.ts src/components/A4Workspace.vue src/components/A4Workspace.test.ts src/components/WorkspaceView.vue src/components/WorkspaceView.test.ts src/components/CoverPage.vue src/style.css
+```
+
+Expected: Diff removes cover data/UI, adds migration, updates tests, and does not include unrelated `index.html`.
+
+- [ ] **Step 6: Commit implementation**
+
+Run:
+
+```bash
+rtk git add src/domain/teachingDesign.ts src/domain/teachingDesign.test.ts server/db.ts server/db.test.ts server/routes/books.test.ts src/composables/useTeachingBook.ts src/composables/useTeachingBook.test.ts src/components/LessonSidebar.vue src/components/LessonSidebar.test.ts src/components/A4Workspace.vue src/components/A4Workspace.test.ts src/components/WorkspaceView.vue src/components/WorkspaceView.test.ts src/components/CoverPage.vue src/style.css
+rtk git commit -m "feat: remove cover page"
+```
+
+Expected: Commit succeeds.