fix: inject app version from package.json instead of hardcoded 1.0.0

- Add Vite define for __APP_VERSION__ from package.json
- Use dynamic version in gateway connect handshake and userAgent
- Show version number in sidebar footer
- Add globals.d.ts type declaration

vite.config.ts

@@ -1,8 +1,12 @@
 import { defineConfig } from 'vite'
 import react from '@vitejs/plugin-react'
 import tailwindcss from '@tailwindcss/vite'
+import pkg from './package.json' with { type: 'json' }
 
 export default defineConfig({
+  define: {
+    __APP_VERSION__: JSON.stringify(pkg.version),
+  },
   plugins: [react(), tailwindcss()],
   build: {
     rollupOptions: {