feat(snap-receiver): add SnapReceiver stub (full implementation in sprint-15 task 8)

scripts/characters/snap_receiver.gd

@@ -0,0 +1,22 @@
+## SnapReceiver — scans for nearby SnapPoints when the parent Character is released.
+## Attach as child of Character. Full implementation connects to DragDropComponent signals.
+class_name SnapReceiver extends Node
+
+const SCAN_RADIUS: float = 80.0
+
+var _current_snap: SnapPoint = null
+var _character: Character
+
+
+func _ready() -> void:
+	_character = get_parent() as Character
+
+
+func get_current_snap() -> SnapPoint:
+	return _current_snap
+
+
+func force_unsnap() -> void:
+	if _current_snap != null:
+		_current_snap.unsnap()
+		_current_snap = null