Assistant: reliable "Nueva conversación" reset

Clearing in place (setMessages + remount) left the conversation
rendered — CopilotKit keeps chat state beyond agent.messages — so the
button now reloads the page after deleting the thread: a fresh boot
hydrates from the empty store and shows the welcome screen with
suggestions, which previously only appeared after a manual refresh.

Supporting changes:
- CopilotChat gets an explicit agentId="wealthysmart" (without it, it
  resolves DEFAULT_AGENT_ID and can bind a different client agent
  instance than useAgent's).
- The BFF answers CopilotChat's POST …/connect with an
  immediately-completed stream: the runtime's in-memory runner replays
  this PROCESS's event history, which resurrects cleared conversations
  and double-feeds hydration. The empty-messages hydration run against
  the DB store is the single restore path.

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

frontend/server.ts

@@ -384,12 +384,28 @@ app.use("*", async (c, next) => {
 });
 
 app.all("/api/copilotkit/*", async (c) => {
+  // CopilotChat fires POST …/agent/<id>/connect for explicit threadIds and
+  // the runtime's in-memory runner replays THIS PROCESS's event history —
+  // stale relative to the DB store (it resurrects cleared conversations and
+  // double-feeds page-load hydration). The empty-messages hydration run
+  // against MAF is our single restore path, so connect gets an
+  // immediately-completed stream instead.
+  if (new URL(c.req.url).pathname.endsWith("/connect")) {
+    return new Response("", {
+      status: 200,
+      headers: { "Content-Type": "text/event-stream" },
+    });
+  }
+
   const cookieHeader = c.req.header("cookie") ?? "";
   const match = cookieHeader.match(/(?:^|;\s*)ws_token=([^;]+)/);
   const token = match?.[1];
   const agentHeaders: Record<string, string> = token
     ? { Authorization: `Bearer ${token}` }
     : {};
+  // Note: the browser's X-Client-Timezone header (set in App.tsx) reaches
+  // the backend without help — CopilotKit's runtime forwards authorization
+  // and all x-* headers to the agent (extractForwardableHeaders).
 
   const agent = new HttpAgent({ url: AGENT_URL, headers: agentHeaders });
   // CK_MIDDLEWARES=off runs the stack bare — used to audit which of these