fix: code review cleanup

- Fixed TypeScript exactOptionalPropertyTypes errors in chat components
- Removed console.error statements (errors are handled via state)
- Fixed type compatibility issues with undefined vs null values
- All chat-related files now pass strict TypeScript checks

apps/web/src/components/chat/ConversationSidebar.tsx

@@ -54,9 +54,9 @@ export const ConversationSidebar = forwardRef<ConversationSidebarRef, Conversati
 
     return {
       id: idea.id,
-      title: idea.title,
-      projectId: idea.projectId,
-      updatedAt: idea.updatedAt,
+      title: idea.title ?? null,
+      projectId: idea.projectId ?? null,
+      updatedAt: idea.updatedAt ?? null,
       messageCount,
     };
   }, []);
@@ -84,7 +84,7 @@ export const ConversationSidebar = forwardRef<ConversationSidebarRef, Conversati
     } catch (err) {
       const errorMsg = err instanceof Error ? err.message : "Failed to load conversations";
       setError(errorMsg);
-      console.error("Error fetching conversations:", err);
+      // Error is set to state and will be displayed to the user
     } finally {
       setIsLoading(false);
     }