feat(snap-point): add SnapPoint node with pose, baby_only filter, and occupant tracking

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

scripts/objects/snap_point.gd

@@ -0,0 +1,42 @@
+## SnapPoint — attachment position on furniture where a Character can snap into a pose.
+## Add to any furniture node. The node auto-registers in the "snap_points" group on _ready.
+class_name SnapPoint extends Node2D
+
+signal character_snapped(character: Character)
+signal character_unsnapped(character: Character)
+
+@export var pose: String = "sitting"
+@export var baby_only: bool = false
+
+var occupant: Character = null
+
+
+func _ready() -> void:
+	add_to_group("snap_points")
+
+
+func is_free() -> bool:
+	return occupant == null
+
+
+func accepts(character: Character) -> bool:
+	if not is_free():
+		return false
+	if not baby_only:
+		return true
+	if character.data == null:
+		return false
+	return character.data.state == CharacterData.State.BABY
+
+
+func snap(character: Character) -> void:
+	occupant = character
+	character_snapped.emit(character)
+
+
+func unsnap() -> void:
+	if occupant == null:
+		return
+	var prev: Character = occupant
+	occupant = null
+	character_unsnapped.emit(prev)

test/unit/test_snap_point.gd

@@ -0,0 +1,75 @@
+## Tests for SnapPoint — attachment node on furniture.
+extends GutTest
+
+const SnapPointScript: GDScript = preload("res://scripts/objects/snap_point.gd")
+
+var _snap: SnapPoint
+var _char: Character
+
+
+func before_each() -> void:
+	_snap = SnapPointScript.new()
+	_snap.pose = "sitting"
+	add_child_autofree(_snap)
+	_char = preload("res://scenes/characters/Character.tscn").instantiate() as Character
+	add_child_autofree(_char)
+
+
+func test_is_free_when_no_occupant() -> void:
+	assert_true(_snap.is_free())
+
+
+func test_is_not_free_when_occupied() -> void:
+	_snap.snap(_char)
+	assert_false(_snap.is_free())
+
+
+func test_snap_sets_occupant() -> void:
+	_snap.snap(_char)
+	assert_eq(_snap.occupant, _char)
+
+
+func test_unsnap_clears_occupant() -> void:
+	_snap.snap(_char)
+	_snap.unsnap()
+	assert_null(_snap.occupant)
+
+
+func test_accepts_any_character_when_baby_only_false() -> void:
+	assert_true(_snap.accepts(_char))
+
+
+func test_does_not_accept_when_occupied() -> void:
+	_snap.snap(_char)
+	var other: Character = preload("res://scenes/characters/Character.tscn").instantiate() as Character
+	add_child_autofree(other)
+	assert_false(_snap.accepts(other))
+
+
+func test_baby_only_rejects_healthy_character() -> void:
+	_snap.baby_only = true
+	var cd: CharacterData = CharacterData.new()
+	cd.state = CharacterData.State.HEALTHY
+	_char.data = cd
+	assert_false(_snap.accepts(_char))
+
+
+func test_baby_only_accepts_baby_state_character() -> void:
+	_snap.baby_only = true
+	var cd: CharacterData = CharacterData.new()
+	cd.state = CharacterData.State.BABY
+	_char.data = cd
+	assert_true(_snap.accepts(_char))
+
+
+func test_snap_emits_character_snapped() -> void:
+	watch_signals(_snap)
+	_snap.snap(_char)
+	assert_signal_emitted(_snap, "character_snapped")
+
+
+func test_unsnap_emits_character_unsnapped() -> void:
+	_snap.snap(_char)
+	watch_signals(_snap)
+	_snap.unsnap()
+	assert_signal_emitted(_snap, "character_unsnapped")