feat: 聊天室模型选择器 + 会话更新 API + 消息部件重构

- 新增 PATCH /api/projects/:id/conversations/:cid 端点，支持更新 modelId 和 title
- 聊天面板新增模型选择下拉框，切换模型自动持久化
- 新建会话时传入默认文本模型 modelId
- 将 ToolCallCard 拆分为 ReasoningPart / TextPart / ToolPart 独立部件
- ToolPart 增加流式状态图标、折叠面板自动展开、错误详情展示
- ReasoningPart 增加思考中/思考完成状态指示
- 补充 PATCH 端点测试：更新成功、跨项目 403、不存在 404、无效 modelId 400

src/server/db/conversations.ts

@@ -2,7 +2,7 @@ import type Database from "bun:sqlite";
 
 import { desc, eq } from "drizzle-orm";
 
-import type { Conversation, Message } from "../../shared/api";
+import type { Conversation, Message, UpdateConversationRequest } from "../../shared/api";
 
 import { paginateQuery, wrap } from "./connection";
 import { conversations, messages, models } from "./schema";
@@ -150,6 +150,33 @@ export function listMessages(
   });
 }
 
+export function updateConversation(
+  raw: Database,
+  id: string,
+  data: UpdateConversationRequest,
+): { conversation: Conversation } | { error: string; status: number } {
+  const db = wrap(raw);
+  const existing = db.select().from(conversations).where(eq(conversations.id, id)).get();
+  if (!existing) return { error: "会话不存在", status: 404 };
+
+  const updates: { modelId?: string; title?: string; updatedAt: string } = { updatedAt: new Date().toISOString() };
+
+  if (data.modelId !== undefined) {
+    const model = db.select().from(models).where(eq(models.id, data.modelId)).get();
+    if (!model) return { error: "模型不存在", status: 400 };
+    updates.modelId = data.modelId;
+  }
+
+  if (data.title !== undefined) {
+    updates.title = data.title;
+  }
+
+  db.update(conversations).set(updates).where(eq(conversations.id, id)).run();
+
+  const row = db.select().from(conversations).where(eq(conversations.id, id)).get();
+  return { conversation: toConversation(row!) };
+}
+
 export function updateConversationTimestamp(raw: Database, id: string): void {
   const db = wrap(raw);
   db.update(conversations).set({ updatedAt: new Date().toISOString() }).where(eq(conversations.id, id)).run();

src/server/routes/chat/update.ts

@@ -0,0 +1,47 @@
+import type Database from "bun:sqlite";
+
+import type { RuntimeMode, UpdateConversationRequest } from "../../../shared/api";
+
+import { getConversation, updateConversation } from "../../db/conversations";
+import { createApiError, jsonResponse } from "../../helpers";
+import { validateIdParam } from "../../middleware";
+
+export async function handleUpdateConversation(req: Request, db: Database, mode: RuntimeMode): Promise<Response> {
+  const url = new URL(req.url);
+  const parts = url.pathname.split("/");
+  const projectId = parts[3];
+  const conversationId = parts[5];
+
+  const validatedProject = validateIdParam(projectId ?? "", mode);
+  if (validatedProject instanceof Response) return validatedProject;
+
+  const validatedConv = validateIdParam(conversationId ?? "", mode);
+  if (validatedConv instanceof Response) return validatedConv;
+
+  const existing = getConversation(db, validatedConv.id);
+  if ("error" in existing) {
+    return jsonResponse(createApiError(existing.error, existing.status), { mode, status: existing.status });
+  }
+
+  if (existing.conversation.projectId !== validatedProject.id) {
+    return jsonResponse(createApiError("会话不属于该项目", 403), { mode, status: 403 });
+  }
+
+  let body: UpdateConversationRequest;
+  try {
+    body = (await req.json()) as UpdateConversationRequest;
+  } catch {
+    return jsonResponse(createApiError("Invalid JSON body", 400), { mode, status: 400 });
+  }
+
+  if (body.modelId === undefined && body.title === undefined) {
+    return jsonResponse(createApiError("至少需要传 modelId 或 title", 400), { mode, status: 400 });
+  }
+
+  const result = updateConversation(db, validatedConv.id, body);
+  if ("error" in result) {
+    return jsonResponse(createApiError(result.error, result.status), { mode, status: result.status });
+  }
+
+  return jsonResponse({ conversation: result.conversation }, { mode });
+}

src/server/server.ts

@@ -201,6 +201,14 @@ export function startServer(options: StartServerOptions) {
           mode,
           logger,
         ),
+        PATCH: withErrorHandler(
+          async (req) => {
+            const { handleUpdateConversation } = await import("./routes/chat/update");
+            return handleUpdateConversation(req, db, mode);
+          },
+          mode,
+          logger,
+        ),
       },
       "/api/projects/:id/conversations/:cid/messages": {
         GET: withErrorHandler(