Expand loop translations and rename max_history

Replace the single "loop" translation with three explicit keys ("loopOff", "loopTrack", "loopQueue") across all language files to support distinct loop modes. Also standardize the settings key from "max-history" to "max_history" and update main.py to read LOG_SETTINGS.get("max_history", 30) for the TimedRotatingFileHandler backupCount. Files changed: langs/*.json, main.py, settings Example.json.

langs/FR.json

@@ -28,7 +28,9 @@
             "resume": "Reprendre",
             "skip": "Passer",
             "leave": "Quitter",
-            "loop": "Boucle",
+            "loopOff": "Désactivé",
+            "loopTrack": "Piste",
+            "loopQueue": "File d'attente",
             "volumeUp": "Volume +",
             "volumeDown": "Volume -",
             "volumeMute": "Muet",