feat: add brand mark component and dashboard page

- Introduced a new `BrandMark` component for branding purposes.
- Created a `DashboardPage` component with a responsive layout, including sections for user profile, apartment management, and API demo.
- Added styles for the dashboard page to enhance user experience.
- Implemented a settings page with theme preferences and session management features.
- Developed a sign-in page with branding and user-friendly design.
- Established a workspace navigation component for easy access to different sections of the application.
- Implemented an `ApartmentService` for managing apartment data with corresponding unit tests.
- Created a `ConfigService` for loading application configuration.
- Added a `ThemeService` to manage user theme preferences dynamically.

frontend/src/app/components/sign-in-page/sign-in-page.ts

@@ -0,0 +1,13 @@
+import { Component, output } from '@angular/core';
+import { MatButtonModule } from '@angular/material/button';
+import { BrandMark } from '../brand-mark';
+
+@Component({
+  selector: 'app-sign-in-page',
+  imports: [BrandMark, MatButtonModule],
+  templateUrl: './sign-in-page.html',
+  styleUrl: './sign-in-page.css',
+})
+export class SignInPage {
+  readonly loginRequested = output<void>();
+}