chore: Fix all lint errors and remove unused code

- Fix 75 ESLint errors by updating eslint.config.mjs:
  - Add missing browser globals (MouseEvent, AbortController, Response, etc.)
  - Add Vite define global (__APP_VERSION__)
  - Configure @ts-nocheck to require descriptions
  - Add no-unused-vars rule for .mjs scripts

- Fix runtime bug in agent-output-modal.tsx (setOutput -> setStreamedContent)

- Remove ~120 unused variable warnings across 97 files:
  - Remove unused imports (React hooks, lucide icons, types)
  - Remove unused constants and variables
  - Remove unused function definitions
  - Prefix intentionally unused parameters with underscore

- Add descriptions to all @ts-nocheck comments (25 files)

- Clean up misc issues:
  - Remove invalid deprecation plugin comments
  - Fix eslint-disable comment placement
  - Add missing RefreshCw import in code-view.tsx

Reduces lint warnings from ~300 to 67 (all remaining are no-explicit-any)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/ui/src/components/views/notifications-view.tsx

@@ -2,13 +2,13 @@
  * Notifications View - Full page view for all notifications
  */
 
-import { useEffect, useCallback } from 'react';
+import { useCallback } from 'react';
 import { useAppStore } from '@/store/app-store';
 import { useNotificationsStore } from '@/store/notifications-store';
 import { useLoadNotifications, useNotificationEvents } from '@/hooks/use-notification-events';
 import { getHttpApiClient } from '@/lib/http-api-client';
 import { Button } from '@/components/ui/button';
-import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card';
+import { Card, CardContent, CardDescription, CardTitle } from '@/components/ui/card';
 import { Bell, Check, CheckCheck, Trash2, ExternalLink } from 'lucide-react';
 import { Spinner } from '@/components/ui/spinner';
 import { useNavigate } from '@tanstack/react-router';
@@ -42,8 +42,6 @@ export function NotificationsView() {
     unreadCount,
     isLoading,
     error,
-    setNotifications,
-    setUnreadCount,
     markAsRead,
     dismissNotification,
     markAllAsRead,