Implement LED test effects with proper cleanup

- Add LED test effects page with multiple test patterns (solid colors, rainbow, breathing, flowing)
- Implement Rust backend for LED test effects with proper task management
- Add automatic cleanup when navigating away from test page using onCleanup hook
- Ensure test mode is properly disabled to resume normal ambient lighting
- Clean up debug logging for production readiness
- Fix menu navigation issues by using SolidJS router components

Features:
- Multiple test patterns: solid colors, rainbow cycle, breathing effect, flowing lights
- Configurable animation speed
- Automatic cleanup prevents LED conflicts with ambient lighting
- Responsive UI with proper error handling

src-tauri/Cargo.lock

@@ -4432,6 +4432,7 @@ dependencies = [
  "tokio",
  "tokio-stream",
  "tokio-tungstenite",
+ "tokio-util",
  "toml 0.7.8",
  "url-build-parse",
 ]