Add kiosk desktop app

Tauri app for the Pi. Media runs through the native LiveKit SDK because
WebKitGTK has no WebRTC, with frames encoded in Rust and drawn to a canvas
under the annotation overlay.

apps/kiosk-client/src-tauri/tauri.conf.json

@@ -0,0 +1,39 @@
+{
+  "$schema": "https://schema.tauri.app/config/2",
+  "productName": "pistation-kiosk",
+  "version": "0.1.0",
+  "identifier": "co.sirblob.pistation",
+  "build": {
+    "beforeDevCommand": "bun run dev",
+    "devUrl": "http://localhost:1420",
+    "beforeBuildCommand": "bun run build",
+    "frontendDist": "../build"
+  },
+  "app": {
+    "windows": [
+      {
+        "title": "PiStation",
+        "width": 1280,
+        "height": 720,
+        "fullscreen": false,
+        "decorations": false,
+        "resizable": true,
+        "focus": true
+      }
+    ],
+    "security": {
+      "csp": null
+    }
+  },
+  "bundle": {
+    "active": true,
+    "targets": ["deb", "appimage"],
+    "icon": [
+      "icons/32x32.png",
+      "icons/128x128.png",
+      "icons/128x128@2x.png",
+      "icons/icon.icns",
+      "icons/icon.ico"
+    ]
+  }
+}