Refactor application structure to use WorkspaceService for state management

- Removed direct state management from components and centralized it in WorkspaceService.
- Updated ApartmentsPage, TenantsPage, LeasesPage, and DashboardPage to utilize WorkspaceService for data handling.
- Introduced SessionService to manage user session state and authentication.
- Simplified component templates to reflect new service-based architecture.
- Removed unused ConfigService and its tests.
- Added lease.html template for lease document generation.
- Created app.routes.spec.ts for route mapping tests.

frontend/src/app/components/dashboard-page/dashboard-page.ts

@@ -1,5 +1,9 @@
-import { Component, input, output } from '@angular/core';
+import { Component, computed, inject, signal } from '@angular/core';
+import { HttpClient } from '@angular/common/http';
+import { Router } from '@angular/router';
 import { MatButtonModule } from '@angular/material/button';
+import { SessionService } from '../../services/session.service';
+import { WorkspaceService } from '../../services/workspace.service';
 
 @Component({
   selector: 'app-dashboard-page',
@@ -8,11 +12,21 @@ import { MatButtonModule } from '@angular/material/button';
   styleUrl: './dashboard-page.css',
 })
 export class DashboardPage {
-  readonly username = input.required<string>();
-  readonly email = input.required<string>();
-  readonly userInitial = input.required<string>();
-  readonly apartmentCount = input.required<number>();
-  readonly helloMessage = input.required<string>();
-  readonly apartmentsRequested = output<void>();
-  readonly connectionCheckRequested = output<void>();
+  private readonly http = inject(HttpClient);
+  private readonly router = inject(Router);
+  readonly session = inject(SessionService);
+  readonly workspace = inject(WorkspaceService);
+  readonly userInitial = computed(() => this.session.username().charAt(0).toUpperCase());
+  readonly helloMessage = signal('');
+
+  constructor() { this.workspace.loadApartments(); }
+
+  checkConnection(): void {
+    this.http.get('/api/hello', { responseType: 'text' }).subscribe({
+      next: (message) => this.helloMessage.set(message),
+      error: (error) => this.helloMessage.set(`Failed to connect to backend: ${error.statusText}`),
+    });
+  }
+
+  showApartments(): void { this.router.navigateByUrl('/apartments'); }
 }