feat(authentication): implement frontend authentication system

- Created auth and user types (T10)
- Implemented API client with token handling (T11)
- Built AuthContext with JWT decoding (T12)
- Added ProtectedRoute component (T13)
- Created LoginPage, RegisterPage, DashboardPage (T14-T16)
- Updated App.tsx with routing and auth provider (T17)
- Added Dockerfile, nginx.conf for frontend deployment (T18-T19)
- Updated docker-compose.yml to include frontend service (T20)
- Updated .gitignore to exclude frontend build artifacts (T21)
- Removed unused App.css (T22)

Refs #2

docker-compose.yml

@@ -34,5 +34,14 @@ services:
       sqlserver:
         condition: service_healthy
 
+  frontend:
+    build:
+      context: ./Frontend
+      dockerfile: Dockerfile
+    ports:
+      - "8181:80"
+    depends_on:
+      - backend
+
 volumes:
   sqlserver_data: