feat: progress notes UI, search/filter, chat backend relay (HQ-21)

- Add progress note input to TaskDetailPanel (textarea + Cmd+Enter submit)
- Add addProgressNote API function
- Add search bar and priority filter to Queue page
- Include chat backend: WebSocket relay (gateway-relay.ts), chat routes (chat.ts)
- Chat frontend updated to connect via backend relay (/api/chat/ws)

frontend/src/lib/api.ts

@@ -115,6 +115,18 @@ export async function deleteProject(id: string): Promise<void> {
   if (!res.ok) throw new Error("Failed to delete project");
 }
 
+// Progress Notes
+export async function addProgressNote(taskId: string, note: string): Promise<Task> {
+  const res = await fetch(`${BASE}/${taskId}/notes`, {
+    method: "POST",
+    credentials: "include",
+    headers: { "Content-Type": "application/json" },
+    body: JSON.stringify({ note }),
+  });
+  if (!res.ok) throw new Error("Failed to add progress note");
+  return res.json();
+}
+
 // Admin API
 export async function fetchUsers(): Promise<any[]> {
   const res = await fetch("/api/admin/users", { credentials: "include" });