Align menu animation to JPCSP (linear tween); capture crashes to log

JPCSP's AbstractAnimAction interpolates linearly and ignores accelMode, so
match that instead of adding easing. Log any uncaught exception from all
threads (video/audio/animator/timer/FX) to /tmp/umd-crash.log to diagnose the
Scenes/Languages crash.

ui/src/main/java/dev/quoije/umd/ui/PlayerApp.java

@@ -492,6 +492,15 @@ public final class PlayerApp extends Application {
     }
 
     public static void main(String[] args) {
+        // Capture any uncaught exception (video/audio/animator/timer/FX threads) to a file.
+        Thread.setDefaultUncaughtExceptionHandler((thread, throwable) -> {
+            try (java.io.PrintWriter writer = new java.io.PrintWriter(new java.io.FileWriter("/tmp/umd-crash.log", true))) {
+                writer.println("=== Uncaught in thread " + thread.getName() + " ===");
+                throwable.printStackTrace(writer);
+            } catch (Exception ignored) {
+            }
+            throwable.printStackTrace();
+        });
         launch(args);
     }
 }