Add sound effects to lever activation and enhance enemy movement detection

sfx/activate_lever.wav.import

@@ -0,0 +1,24 @@
+[remap]
+
+importer="wav"
+type="AudioStreamWAV"
+uid="uid://beq14we7v3iw4"
+path="res://.godot/imported/activate_lever.wav-87766fea9595f0ffc6f921a9a8c2ed8f.sample"
+
+[deps]
+
+source_file="res://sfx/activate_lever.wav"
+dest_files=["res://.godot/imported/activate_lever.wav-87766fea9595f0ffc6f921a9a8c2ed8f.sample"]
+
+[params]
+
+force/8_bit=false
+force/mono=false
+force/max_rate=false
+force/max_rate_hz=44100
+edit/trim=false
+edit/normalize=false
+edit/loop_mode=0
+edit/loop_begin=0
+edit/loop_end=-1
+compress/mode=0