feat: integrate angular-oauth2-oidc for authentication

- Added angular-oauth2-oidc package to package.json.
- Configured OAuth client in app.config.ts with resource server settings.
- Implemented login component with basic HTTP request to fetch products.
- Set up routing for the login component.
- Updated app component to initialize OAuth service and handle login.
- Modified default app settings to open and collapse sidenav by default.
- Removed placeholder content from app.html to streamline the initial view.

Web/package.json

@@ -26,6 +26,7 @@
     "@angular/forms": "^20.0.0",
     "@angular/platform-browser": "^20.0.0",
     "@angular/router": "^20.0.0",
+    "angular-oauth2-oidc": "^20.0.2",
     "rxjs": "~7.8.0",
     "tslib": "^2.3.0"
   },