fix: defer chat badge autorun to avoid module-init TDZ crash

The badge autorun fired synchronously inside the ChatStore constructor,
which runs at module load. Auto-imported globals used in setBadge ->
getTotalCounters (U.Space) were not yet initialized in some module
evaluation orders, causing a "Cannot access 'tt' before initialization"
ReferenceError from MobX. Schedule the autorun via queueMicrotask so
all top-level module evaluation finishes first, while still binding
before any user interaction.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: ra3orblade

src/ts/store/chat.ts

@@ -25,7 +25,7 @@ class ChatStore {
 			discussionParentMapDelete: action,
 		});
 
-		autorun(() => this.setBadge());
+		queueMicrotask(() => autorun(() => this.setBadge()));
 	};
 
 	/**