fix: recover chat state after idle reconnects

Resyncs active sessions after hidden upstream stream reconnects
Recovers orphaned streaming parts with active-session snapshots
Adds coverage for event-stream reconnect behavior

packages/web/server/lib/event-stream/global-ws-bridge.js

@@ -120,6 +120,17 @@ export function createGlobalMessageStreamWsBridge({
       for (const socket of Array.from(clients)) {
         if (!readyClients.has(socket)) {
           markReady(socket, clientLastEventIds.get(socket) ?? '');
+          continue;
+        }
+
+        if (status.wasReady) {
+          const sent = sendMessageStreamWsFrame(socket, {
+            type: 'ready',
+            scope: 'global',
+          });
+          if (!sent) {
+            removeClient(socket);
+          }
         }
       }
       return;

packages/web/server/lib/event-stream/runtime.test.js

@@ -435,7 +435,7 @@ describe('message stream websocket runtime', () => {
 
         return createSseResponse({
           signal: options.signal,
-          holdOpen: false,
+          holdOpen: true,
           blocks: [
             'id: evt-2\ndata: {"type":"server.connected","properties":{}}\n\n',
           ],
@@ -451,7 +451,7 @@ describe('message stream websocket runtime', () => {
     const readyFrames = socket.sent.filter((frame) => frame.type === 'ready');
     const eventFrames = socket.sent.filter((frame) => frame.type === 'event' && frame.payload?.type === 'server.connected');
 
-    expect(readyFrames).toHaveLength(1);
+    expect(readyFrames.length).toBeGreaterThanOrEqual(2);
     expect(eventFrames.length).toBeGreaterThanOrEqual(2);
     expect(fetchCalls.slice(0, 2)).toEqual([null, 'evt-1']);
     expect(triggerHealthCheckCalls).toBe(0);