feat: integrate FontAwesome icons across various components

- Updated apartment-list component to use FontAwesome icons for better visual representation.
- Refactored brand-mark component to utilize FontAwesome for the brand icon.
- Enhanced dashboard-page with FontAwesome icons for improved navigation.
- Replaced SVG icons with FontAwesome in settings-page for consistency and better performance.
- Updated sign-in-page to use FontAwesome for the sign-in action icon.
- Refactored tenant-card to incorporate FontAwesome icons for attachments.
- Enhanced workspace-navigation with FontAwesome icons for all navigation items.
- Applied consistent styling for fa-icon elements across components.

frontend/src/styles.scss

@@ -98,6 +98,14 @@ svg {
   display: block;
 }
 
+fa-icon {
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  line-height: 1;
+  vertical-align: middle;
+}
+
 h1,
 h2,
 h3,