Add administrative room close and reopen controls

Preserve readable private tables, discussion and pending games while closure blocks new play, joins, messages, AI and seat mutations. Add live-authorized atomic closure audits, room-version/revision fences, dedicated controls and exact saved retries. Reopen with the saved pause/join settings and current credentials; restoring a removed but closed room keeps its AI stopped.

Verified types, lint, 5356 offline tests, 52 HTTP tests and build. Seventeen dedicated authenticated HTTP groups and independent privacy/persistence review passed. Desktop/mobile browser QA confirmed one close after a lost response and refresh, persistent readable notices, retained private draft, mobile reopening and saved-seat refresh. All 2,001 baseline rooms, 4,243 seats and related records preserved. Positive production admin acceptance awaits authorized QA access; full admin and rules gates remain open.

tests/client-request.test.ts

@@ -276,3 +276,10 @@ void test('a failed gateway response keeps its status and requires reconciliatio
   );
   assert.equal(calls, 1);
 });
+
+void test('a typed closure rejection retains possibly completed request proof without treating it as removal', async () => {
+  const { isRoomClosed, isRoomRemoved, requestMayHaveCompleted } = await import('../lib/client-request');
+  const error = new ClientRequestError('Room closed', 'http', 409, 'ROOM_CLOSED');
+  assert.equal(isRoomClosed(error), true); assert.equal(isRoomRemoved(error), false);
+  assert.equal(requestMayHaveCompleted(error), true);
+});