Migrate frontend realtime messaging to SSE.

Switch service integrations and screen/store consumers from websocket events to SSE, and ignore generated dist-web artifacts.

Made-with: Cursor

src/services/database.ts

@@ -459,9 +459,21 @@ export const deleteMessage = async (messageId: string): Promise<void> => {
 };
 
 // 更新消息状态（如撤回）
-export const updateMessageStatus = async (messageId: string, status: string): Promise<void> => {
+// clearContent=true 时，会同时清空本地存储的消息内容与 segments，仅保留状态占位
+export const updateMessageStatus = async (
+  messageId: string,
+  status: string,
+  clearContent: boolean = false
+): Promise<void> => {
   await enqueueWrite(async () => {
     const database = await getDb();
+    if (clearContent) {
+      await database.runAsync(
+        `UPDATE messages SET status = ?, content = '', segments = '[]' WHERE id = ?`,
+        [status, messageId]
+      );
+      return;
+    }
     await database.runAsync(
       `UPDATE messages SET status = ? WHERE id = ?`,
       [status, messageId]