feat: Add WFW-Aushang web app with PWA support, offline caching, and dark mode

- Created index.html for the main application interface with responsive design and dark mode support.
- Added manifest.webmanifest for PWA configuration, including app icons and display settings.
- Implemented service worker (sw.js) for offline caching of assets and network-first strategy for versioning.
- Introduced version.json to manage app versioning.

config/.htaccess

@@ -0,0 +1,3 @@
+<Files "config.json">
+  Require all denied
+</Files>

config/config.json

@@ -0,0 +1,6 @@
+{
+  "auth": {
+    "user": "Thomas",
+    "pass": "Alles4Mich!"
+  }
+}