fix: screenshare rendering, voice panel layout, SW cache bust with git SHA

- VideoGrid: add screen share track display with proper sizing
- participantToVoice: detect ScreenShare + ScreenShareAudio tracks
- VoicePanel: flex layout, no scroll, tiles dynamically fill space
- VoiceChannel: show screen/camera icons in participant list
- vite.config: inject git SHA into SW CACHE_VERSION on build

web/vite.config.ts

@@ -1,6 +1,8 @@
 import { defineConfig } from 'vite'
 import react from '@vitejs/plugin-react'
 import { execSync } from 'child_process'
+import fs from 'fs'
+import path from 'path'
 
 let gitSha = process.env.GIT_SHA
 if (!gitSha) {
@@ -13,7 +15,23 @@ if (!gitSha) {
 
 // https://vite.dev/config/
 export default defineConfig({
-  plugins: [react()],
+  plugins: [
+    react(),
+    // Inject git SHA into service worker cache version so every deploy busts the SW cache
+    {
+      name: 'inject-sw-version',
+      writeBundle() {
+        const swPath = path.resolve(__dirname, 'dist/sw.js');
+        if (!fs.existsSync(swPath)) return;
+        let content = fs.readFileSync(swPath, 'utf-8');
+        content = content.replace(
+          /const CACHE_VERSION = '[^']*'/,
+          `const CACHE_VERSION = 'dumpster-${gitSha}'`
+        );
+        fs.writeFileSync(swPath, content);
+      },
+    },
+  ],
   define: {
     __APP_VERSION__: JSON.stringify(`v${gitSha}`),
   },