feat(items): add OutfitItem, tap-to-undress, and outfit refs on Character

- Add OutfitItem (extends HoldableItem): applies outfit on drop within 80px
  of character body, falls back to hand slot attach if no character in range
- Add apply_outfit_item / remove_outfit / _handle_outfit_tap to Character
- Track item node refs in _outfit_item_refs for restoring visibility
- Fix animation state: reset to idle before tap handling in _on_drag_released
- Extract _ITEM_DROP_OFFSET constant (replaces magic Vector2(0,60))
- Add 5 tests in test_outfit_item.gd, 14 new tests in test_character_v2.gd

scripts/objects/outfit_item.gd

@@ -0,0 +1,31 @@
+## OutfitItem — HoldableItem that applies an outfit layer to a Character when dropped
+## within OUTFIT_APPLY_RADIUS of the character's center. Falls back to hand slot
+## attachment if no character body is in range.
+class_name OutfitItem extends HoldableItem
+
+const OUTFIT_APPLY_RADIUS: float = 80.0
+
+@export var outfit_layer: int = 1
+@export var outfit_sprite: Texture2D
+
+
+func _on_drag_released(_pos: Vector2) -> void:
+	var character: Character = _find_nearest_character()
+	if character != null:
+		character.apply_outfit_item(outfit_layer, item_id, outfit_sprite, self)
+		return
+	super._on_drag_released(_pos)
+
+
+func _find_nearest_character() -> Character:
+	var best_dist: float = OUTFIT_APPLY_RADIUS
+	var best: Character = null
+	for node: Node in get_tree().get_nodes_in_group("characters"):
+		var character: Character = node as Character
+		if character == null:
+			continue
+		var dist: float = global_position.distance_to(character.global_position)
+		if dist < best_dist:
+			best_dist = dist
+			best = character
+	return best