add angular login via keycloak

[Mankianer]

This pull request introduces several changes to integrate OpenID Connect (OIDC) authentication into the Angular client application. The major changes include modifications to the environment configurations, updates to the application routes, and the addition of new services and components to handle authentication.

Authentication Integration:

• Added angular-auth-oidc-client dependency to client/package.json.
• Created auth-config.ts to load OIDC configuration dynamically based on the environment.
• Implemented LoginService to manage authentication logic including login, logout, and session refresh.

Environment Configuration:

• Updated angular.json to include file replacements for different environments and added proxy configuration [1] [2].
• Added environment.ts and environment.development.ts to define environment-specific settings [1] [2].

Application Routing:

• Modified app.routes.ts to include new routes for home and logged-out components and added route guards for protected routes.
• Updated app.config.ts to provide HTTP interceptors and OIDC configuration.

New Components:

• Added HomeComponent to serve as the landing page after login and handle login/logout actions [1] [2] [3].
• Added LoggedOutComponent to display a message when the user is logged out [1] [2] [3].

These changes collectively enhance the application's security by integrating OIDC for user authentication and managing different environments effectively.