When eval receives invalid GDScript, script.reload() triggers a debugger
break that halts the game loop permanently (especially with LocalDebugger
which doesn't respect skip_breakpoints). Two-layer defense:
1. On startup, attempt to disable debugger breaks via
EngineDebugger.send_message (works for RemoteDebugger)
2. When debugger is unsafe (LocalDebugger), validate eval code in an
external headless Godot process before executing it in-process
