feat(setup): bootstrap Android plugin and web UI

This initial commit adds a multi-part scaffold for Wechselbild, including a web UI and an Android plugin.
It introduces frontend assets and a package.json-based dev setup, plus plugin scaffolding for Android with Kotlin sources and Cargo.toml for the Tauri plugin.

- Adds Android wallpaper plugin with Kotlin sources and manifest
- Includes web UI scaffold with index.html and package.json
- Adds Tauri plugin scaffold with Cargo.toml and build config

plugins/permissions/autogenerated/reference.md

@@ -0,0 +1,124 @@
+## Default Permission
+
+Allow the Wechselbild app to manage its wallpaper collection
+
+#### This default permission set includes the following:
+
+- `allow-get-state`
+- `allow-select-images`
+- `allow-set-setting`
+- `allow-next-wallpaper`
+
+## Permission Table
+
+<table>
+<tr>
+<th>Identifier</th>
+<th>Description</th>
+</tr>
+
+
+<tr>
+<td>
+
+`wallpaper:allow-get-state`
+
+</td>
+<td>
+
+Enables the get_state command without any pre-configured scope.
+
+</td>
+</tr>
+
+<tr>
+<td>
+
+`wallpaper:deny-get-state`
+
+</td>
+<td>
+
+Denies the get_state command without any pre-configured scope.
+
+</td>
+</tr>
+
+<tr>
+<td>
+
+`wallpaper:allow-next-wallpaper`
+
+</td>
+<td>
+
+Enables the next_wallpaper command without any pre-configured scope.
+
+</td>
+</tr>
+
+<tr>
+<td>
+
+`wallpaper:deny-next-wallpaper`
+
+</td>
+<td>
+
+Denies the next_wallpaper command without any pre-configured scope.
+
+</td>
+</tr>
+
+<tr>
+<td>
+
+`wallpaper:allow-select-images`
+
+</td>
+<td>
+
+Enables the select_images command without any pre-configured scope.
+
+</td>
+</tr>
+
+<tr>
+<td>
+
+`wallpaper:deny-select-images`
+
+</td>
+<td>
+
+Denies the select_images command without any pre-configured scope.
+
+</td>
+</tr>
+
+<tr>
+<td>
+
+`wallpaper:allow-set-setting`
+
+</td>
+<td>
+
+Enables the set_setting command without any pre-configured scope.
+
+</td>
+</tr>
+
+<tr>
+<td>
+
+`wallpaper:deny-set-setting`
+
+</td>
+<td>
+
+Denies the set_setting command without any pre-configured scope.
+
+</td>
+</tr>
+</table>