Fix: lots of various fixes

src/engine/realtime.rs

@@ -148,6 +148,17 @@ pub fn set_realtime_priority() -> bool {
     false
 }
 
+#[cfg(target_os = "linux")]
+pub fn warn_no_rt(thread_name: &str) {
+    eprintln!(
+        "[cagire] Warning: No realtime priority for {thread_name} thread. \
+         Add user to 'audio' group and configure rtprio limits."
+    );
+}
+
+#[cfg(not(target_os = "linux"))]
+pub fn warn_no_rt(_thread_name: &str) {}
+
 /// High-precision sleep using clock_nanosleep on Linux.
 /// Uses monotonic clock for jitter-free sleeping.
 #[cfg(target_os = "linux")]