feat: F5.3b the editor on a project of server F

?project=<uuid> opens the shared document over /sync and the room over
/sim (RemoteSimHost: messages wait for the socket, a lost socket comes
back with what it watched, F's refusal or parting ends it); instead of
the editor, a word why when F refuses or lets go. F tells each
connection its access at once. Who only reads sees everything and
changes nothing: no palette or undo, a locked surface, the sheet's
fields disabled (tabs stay), no starting or stopping; thawed, the
document comes anew. The toolbar names who started the simulation.
Refusals carry no message, so Hocuspocus writes nothing outside F's
JSON log. A browser test runs three people against a real F.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/server/test/sim.test.ts

@@ -220,7 +220,8 @@ describe('a simulation room on F', () => {
     again.send({ kind: 'input', node: node('Notebook 1.10'), app: 'terminal', action: 'enter', args: { line: 'touch left.txt' }, reqId: 'r' });
     await until(() => again.got.some((message) => message.kind === 'ack'));
     again.socket.close();
-    await until(() => server.sims.stats().rooms === 0, 5_000);
+    await until(() => server.log.lines.some((line) => line.event === 'sim.roomClosed'), 5_000);
+    expect(server.sims.stats().rooms).toBe(0);
     expect(server.log.lines.filter((line) => line.event === 'sim.roomClosed')).toEqual([{ level: 'info', event: 'sim.roomClosed', project, writeBack: true }]);
     // The document let go once the room had written back.
     await until(() => server.sync.hocuspocus.getDocumentsCount() === 0);