Convert project to TypeScript; add workflow to build with Vite then publish to GH Pages.

web/public/manifest.json

@@ -0,0 +1,23 @@
+{
+  "name": "PANDORA chat",
+  "short_name": "PANDORA",
+  "theme_color": "#ffffff",
+  "background_color": "#102457",
+  "display": "standalone",
+  "orientation": "any",
+  "scope": "./",
+  "start_url": "./",
+  "description": "Internet messaging",
+  "icons": [
+    {
+      "src": "icon-192.png",
+      "sizes": "192x192",
+      "type": "image/png"
+    },
+    {
+      "src": "icon-512.png",
+      "sizes": "512x512",
+      "type": "image/png"
+    }
+  ]
+}