feat: Frontend CSS refactoring and test improvements

Frontend:
- Refactored CSS architecture with new utility classes
- Updated dashboard components styling
- Improved responsive grid system
- Enhanced typography and variables
- Updated E2E and integration tests

Added:
- Claude Code slash commands for validation
- SSH tunnel and start test scripts

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

reports-app/frontend/tests/integration/global-setup.js

@@ -3,10 +3,10 @@
  * Ensures SSH tunnel and backend services are running
  */
 
-import path from 'path';
-import { fileURLToPath } from 'url';
-const __filename = fileURLToPath(import.meta.url);
-const __dirname = path.dirname(__filename);
+// import path from 'path';
+// import { fileURLToPath } from 'url';
+// const __filename = fileURLToPath(import.meta.url);
+// const __dirname = path.dirname(__filename);
 
 export default async function globalSetup() {
   console.log('🔧 Setting up real API integration test environment...');