chore(格式): Prettier 统一到全仓，后端和契约一次性格式化

原来只有 `apps/web` 在 Prettier 下（配置在 `apps/web/.prettierrc.toml`、脚本在
web 的 package.json），后端和契约从来没格式化过 —— 手写在 100 列上下，`db/schema.ts`
还是 drizzle-kit pull 留下的 tab 缩进。两套口径分叉久了，跨端改一处就得记着「这边
什么风格」。

- 配置搬到根目录 `.prettierrc.toml`，内容不变（`semi=false`，其余全默认，
  printWidth 80 —— 和前端已有的格式一致，不另立一套宽度）；
- 脚本统一成根目录 `bun run fmt`，覆盖 `apps/*/src`、`apps/web/tests` 和两个构建
  配置；web 自己那份 `fmt` 和重复的 prettier 依赖删掉；
- `.prettierignore` 挡掉两类不该碰的：drizzle-kit 生成的 `src/db/meta/` 结构快照
  （它是 db:generate 的比对输入，只该由 drizzle-kit 写）、unplugin 每次 dev 都会
  重写的 `auto-imports.d.ts` / `components.d.ts`；
- 全量跑了一遍。纯格式，无行为改动：api typecheck / check:routes / check:ast、
  前端 type-check 全过，起 api 打了接口确认正常。前端这 39 个文件的小改动是
  prettier 版本漂移（类型断言的换行口径变了），不是新配置带来的。

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

apps/api/src/services/ai.ts

@@ -27,14 +27,27 @@ export async function completeChat(system: string, user: string) {
   const response = await fetch(new URL("/chat/completions", config.aiBaseUrl), {
     method: "POST",
     signal: AbortSignal.timeout(COMPLETE_TIMEOUT_MS),
-    headers: { "content-type": "application/json", authorization: `Bearer ${config.aiKey}` },
-    body: JSON.stringify(requestBody([
-      { role: "system", content: system },
-      { role: "user", content: user },
-    ], false)),
+    headers: {
+      "content-type": "application/json",
+      authorization: `Bearer ${config.aiKey}`,
+    },
+    body: JSON.stringify(
+      requestBody(
+        [
+          { role: "system", content: system },
+          { role: "user", content: user },
+        ],
+        false,
+      ),
+    ),
   })
-  if (!response.ok) throw new Error(`AI provider returned HTTP ${response.status}: ${await response.text()}`)
-  const payload = await response.json() as { choices?: Array<{ message?: { content?: string } }> }
+  if (!response.ok)
+    throw new Error(
+      `AI provider returned HTTP ${response.status}: ${await response.text()}`,
+    )
+  const payload = (await response.json()) as {
+    choices?: Array<{ message?: { content?: string } }>
+  }
   return payload.choices?.[0]?.message?.content?.trim() ?? ""
 }
 
@@ -48,21 +61,37 @@ export function streamChat(
     async start(controller) {
       const send = (value: string) => controller.enqueue(encoder.encode(value))
       if (!config.aiKey) {
-        send(`data: ${JSON.stringify({ type: "error", message: "缺少 AI_KEY" })}\n\n`)
+        send(
+          `data: ${JSON.stringify({ type: "error", message: "缺少 AI_KEY" })}\n\n`,
+        )
         send("event: end\n\n")
         controller.close()
         return
       }
       try {
-        const response = await fetch(new URL("/chat/completions", config.aiBaseUrl), {
-          method: "POST",
-          headers: { "content-type": "application/json", authorization: `Bearer ${config.aiKey}` },
-          body: JSON.stringify(requestBody([
-            { role: "system", content: system },
-            { role: "user", content: user },
-          ], true)),
-        })
-        if (!response.ok || !response.body) throw new Error(`AI provider returned HTTP ${response.status}: ${await response.text()}`)
+        const response = await fetch(
+          new URL("/chat/completions", config.aiBaseUrl),
+          {
+            method: "POST",
+            headers: {
+              "content-type": "application/json",
+              authorization: `Bearer ${config.aiKey}`,
+            },
+            body: JSON.stringify(
+              requestBody(
+                [
+                  { role: "system", content: system },
+                  { role: "user", content: user },
+                ],
+                true,
+              ),
+            ),
+          },
+        )
+        if (!response.ok || !response.body)
+          throw new Error(
+            `AI provider returned HTTP ${response.status}: ${await response.text()}`,
+          )
         send("event: start\n\n")
         const reader = response.body.getReader()
         const decoder = new TextDecoder()
@@ -79,7 +108,12 @@ export function streamChat(
             const data = line.slice(5).trim()
             if (data === "[DONE]") continue
             try {
-              const item = JSON.parse(data) as { choices?: Array<{ delta?: { content?: string }; finish_reason?: string | null }> }
+              const item = JSON.parse(data) as {
+                choices?: Array<{
+                  delta?: { content?: string }
+                  finish_reason?: string | null
+                }>
+              }
               const choice = item.choices?.[0]
               const content = choice?.delta?.content
               if (content) {
@@ -96,7 +130,9 @@ export function streamChat(
         if (onComplete) await onComplete(full)
         send(`data: ${JSON.stringify({ type: "done" })}\n\n`)
       } catch (error) {
-        send(`data: ${JSON.stringify({ type: "error", message: error instanceof Error ? error.message : String(error) })}\n\n`)
+        send(
+          `data: ${JSON.stringify({ type: "error", message: error instanceof Error ? error.message : String(error) })}\n\n`,
+        )
       } finally {
         send("event: end\n\n")
         controller.close()