Replace all `lock().unwrap()` calls on Mutex guards with explicit error messages using `.expect("... mutex poisoned")`. This improves robustness by providing clear diagnostics when a thread panics while holding the lock, preventing silent failures. Affected modules: events.rs (Renderer/MediaServer), all renderer backends, queue backend/implementation files. Also adds documentation to marker traits (HasQueue、 HasContinuousStream) and clarifies error handling in watcher loop with panic catching.
Eric Coissac
4b793cec59