refactor(题目): 比赛和题单改用题库那个编辑器——题单里的求助终于接得上，一键换中文标点也能用了

比赛和题单原来用的是另一个精简版编辑器（BasicEditor），没有协作绑定、也没有
错误标记扩展：题单里学生点「求助」，老师接单后编辑器绑不上；比赛和题单里
「把中文标点都换成英文」点了没反应、出错行也不标红。三种入口统一成 ProblemEditor，
删掉 BasicEditor。流程图仍然只在题库入口出现（语言列表那道闸没动）。

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

apps/web/src/oj/problem/components/BasicEditor.vue

@@ -1,71 +0,0 @@
-<script lang="ts" setup>
-import { storeToRefs } from "pinia"
-import { useCodeStore } from "oj/store/code"
-import { useProblemStore } from "oj/store/problem"
-import { SOURCES } from "utils/constants"
-import CodeEditor from "shared/components/CodeEditor.vue"
-import { useBreakpoints } from "shared/composables/breakpoints"
-import storage from "utils/storage"
-import type { LANGUAGE } from "utils/types"
-import { beginEditTrace, editTraceExtensions } from "oj/problem/utils/editTrace"
-import EditorToolbar from "./EditorToolbar.vue"
-
-const route = useRoute()
-
-const codeStore = useCodeStore()
-const problemStore = useProblemStore()
-const { problem } = storeToRefs(problemStore)
-
-const { isDesktop } = useBreakpoints()
-
-const contestID = route.params.contestID || null
-const storageKey = computed(
-  () => `problem_${problem.value!._id}_contest_${contestID}_lang_${codeStore.code.language}`,
-)
-
-const editorHeight = computed(() =>
-  isDesktop.value ? "calc(100vh - 133px)" : "calc(100vh - 172px)",
-)
-
-function loadCode() {
-  codeStore.code.language = problemStore.supportedLanguage(codeStore.code.language)
-  const savedCode = storage.get(storageKey.value)
-  codeStore.setCode(
-    savedCode ||
-      problem.value!.template[codeStore.code.language] ||
-      SOURCES[codeStore.code.language],
-  )
-  beginEditTrace(`problem_${problem.value!._id}_contest_${contestID}`, codeStore.code.value.length)
-}
-
-onMounted(loadCode)
-
-// 换题时组件复用、不重新挂载，和 ProblemEditor 一样得自己重新载入
-watch(() => problem.value?._id, loadCode)
-
-const changeCode = (v: string) => {
-  storage.set(storageKey.value, v)
-}
-
-const changeLanguage = (v: LANGUAGE) => {
-  const savedCode = storage.get(storageKey.value)
-  codeStore.setCode(
-    savedCode && storageKey.value.split("_").pop() === v
-      ? savedCode
-      : problem.value!.template[codeStore.code.language] || SOURCES[codeStore.code.language],
-  )
-}
-</script>
-
-<template>
-  <n-flex vertical>
-    <EditorToolbar :storage-key="storageKey" @change-language="changeLanguage" />
-    <CodeEditor
-      v-model:value="codeStore.code.value"
-      :language="codeStore.code.language"
-      :height="editorHeight"
-      :extra-extensions="editTraceExtensions"
-      @update:model-value="changeCode"
-    />
-  </n-flex>
-</template>