feat: implement frontend video platform configuration and abstraction

- Add NEXT_PUBLIC_VIDEO_PLATFORM environment variable support
- Create video platform abstraction layer with factory pattern
- Implement Whereby and Jitsi platform providers
- Update room meeting page to use platform-agnostic component
- Add platform display in room management (cards and table views)
- Support single platform per deployment configuration
- Maintain backward compatibility with existing Whereby integration

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

www/app/lib/videoPlatforms/utils.ts

@@ -0,0 +1,23 @@
+import { VideoPlatform } from "../../api";
+
+export const getPlatformDisplayName = (platform?: VideoPlatform): string => {
+  switch (platform) {
+    case "whereby":
+      return "Whereby";
+    case "jitsi":
+      return "Jitsi Meet";
+    default:
+      return "Whereby"; // Default fallback
+  }
+};
+
+export const getPlatformColor = (platform?: VideoPlatform): string => {
+  switch (platform) {
+    case "whereby":
+      return "blue";
+    case "jitsi":
+      return "green";
+    default:
+      return "blue"; // Default fallback
+  }
+};