feat: Implement Easter egg for music inspiration in credits page

- Added click handler for Easter egg that enables music inspiration feature.
- Updated credits page to include new icons and handle click events.
- Enhanced inspiration page to fetch and display Spotify track embed HTML.
- Refactored inspiration loading logic to include track data.
- Introduced theme selection in settings with light and dark modes.
- Updated settings page to reflect new theme options and improve toast messages.
- Refined layout styles across various pages for consistent theming.
- Bumped application version to 1.5.0 in installer script.

frontend/src/routes/+layout.svelte

@@ -1,6 +1,7 @@
 <script lang="ts">
 	import { onMount } from 'svelte';
 	import { setupConsoleLogger } from '$lib/utils/logger-hook';
+	import "./layout.css";
 
 	let { children } = $props();