feat(core): implement room navigation, character states, save/load and settings menu

- RoomNavigator autoload: smooth camera pan between floors
- Floor1 and Floor2 placeholder rooms with elevator buttons
- CharacterData Resource with State enum (HEALTHY/SICK/SLEEPING/TIRED)
- Character visual state feedback via ColorRect color
- Main scene loads saved state on startup
- SettingsMenu with music/sfx sliders and game reset
- HUD settings button to open SettingsMenu

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

scripts/characters/character.gd

@@ -3,18 +3,55 @@ class_name Character extends Node2D
 
 signal character_picked_up(character: Character)
 signal character_placed(character: Character, position: Vector2)
+signal state_changed(new_state: CharacterData.State)
 
 @export var character_id: String = ""
 @export var display_name: String = ""
+@export var data: CharacterData
 
 var _is_held: bool = false
 
+const _STATE_COLORS: Dictionary = {
+	CharacterData.State.HEALTHY: Color(0.6, 0.8, 1.0),
+	CharacterData.State.SICK: Color(0.7, 0.9, 0.7),
+	CharacterData.State.SLEEPING: Color(0.8, 0.7, 0.95),
+	CharacterData.State.TIRED: Color(1.0, 0.95, 0.6),
+	CharacterData.State.PREGNANT: Color(1.0, 0.85, 0.9),
+	CharacterData.State.BABY: Color(0.9, 0.95, 1.0),
+}
+
 
 func _ready() -> void:
 	var drag: DragDropComponent = get_node_or_null("DragDropComponent") as DragDropComponent
 	if drag != null:
 		drag.drag_picked_up.connect(_on_drag_picked_up)
 		drag.drag_released.connect(_on_drag_released)
+	if data != null:
+		_update_visual_state()
+
+
+func set_state(new_state: CharacterData.State) -> void:
+	if data == null:
+		return
+	data.state = new_state
+	_update_visual_state()
+	state_changed.emit(new_state)
+
+
+func _update_visual_state() -> void:
+	if data == null:
+		return
+	var visual: ColorRect = get_node_or_null("Visual") as ColorRect
+	if visual == null:
+		return
+	var color: Color = _STATE_COLORS.get(data.state, Color(0.6, 0.8, 1.0))
+	visual.color = color
+	var ear_left: ColorRect = get_node_or_null("Ears/EarLeft") as ColorRect
+	var ear_right: ColorRect = get_node_or_null("Ears/EarRight") as ColorRect
+	if ear_left != null:
+		ear_left.color = color
+	if ear_right != null:
+		ear_right.color = color
 
 
 func _on_drag_picked_up(_pos: Vector2) -> void:

scripts/characters/character_data.gd

@@ -0,0 +1,12 @@
+## CharacterData — Resource holding all persistent state for one character.
+class_name CharacterData extends Resource
+
+enum State { HEALTHY, SICK, SLEEPING, TIRED, PREGNANT, BABY }
+enum Species { BUNNY, KITTEN }
+
+@export var id: String = ""
+@export var display_name: String = ""
+@export var species: Species = Species.BUNNY
+@export var state: State = State.HEALTHY
+@export var current_floor: int = 0
+@export var position: Vector2 = Vector2.ZERO

scripts/main/main.gd

@@ -0,0 +1,16 @@
+## Main — scene root: wires up RoomNavigator and restores saved character positions.
+extends Node2D
+
+
+func _ready() -> void:
+	RoomNavigator.initialize($Camera2D)
+	SaveManager.load_game()
+	_apply_saved_state()
+
+
+func _apply_saved_state() -> void:
+	for character in $Characters.get_children():
+		if character is Character and character.data != null:
+			var pos: Vector2 = GameState.get_character_position(character.data.id)
+			if pos != Vector2.ZERO:
+				character.global_position = pos

scripts/objects/elevator_button.gd

@@ -0,0 +1,30 @@
+## ElevatorButton — tappable button that navigates the camera to a target floor.
+class_name ElevatorButton extends Node2D
+
+@export var target_floor: int = 0
+
+var _area: Area2D
+
+
+func _ready() -> void:
+	_area = get_node_or_null("CollisionArea") as Area2D
+	if _area != null:
+		_area.input_event.connect(_on_input_event)
+
+
+func _on_input_event(_viewport: Node, event: InputEvent, _shape_idx: int) -> void:
+	if event is InputEventMouseButton and event.pressed and event.button_index == MOUSE_BUTTON_LEFT:
+		_on_pressed()
+	elif event is InputEventScreenTouch and event.pressed:
+		_on_pressed()
+
+
+func _on_pressed() -> void:
+	RoomNavigator.go_to_floor(target_floor)
+	_play_bounce()
+
+
+func _play_bounce() -> void:
+	var tween: Tween = create_tween()
+	tween.tween_property(self, "scale", Vector2(1.15, 1.15), 0.08)
+	tween.tween_property(self, "scale", Vector2(1.0, 1.0), 0.08)

scripts/systems/hud.gd

@@ -1,10 +1,11 @@
-## HUD — heads-up display with back button and music toggle.
+## HUD — heads-up display with back button, music toggle, and settings access.
 extends CanvasLayer
 
 const MUSIC_ON_SYMBOL: String = "♪"
 const MUSIC_OFF_SYMBOL: String = "✕"
 
 var _music_enabled: bool = true
+@onready var _settings_menu: SettingsMenu = get_node_or_null("/root/Main/UI/SettingsMenu") as SettingsMenu
 
 
 func _on_back_button_pressed() -> void:
@@ -18,3 +19,8 @@ func _on_music_toggle_pressed() -> void:
 	var btn: Button = get_node_or_null("MusicToggle") as Button
 	if btn != null:
 		btn.text = MUSIC_ON_SYMBOL if _music_enabled else MUSIC_OFF_SYMBOL
+
+
+func _on_settings_button_pressed() -> void:
+	if _settings_menu != null:
+		_settings_menu.show_menu()

scripts/systems/room_navigator.gd

@@ -0,0 +1,30 @@
+## RoomNavigator — autoload that moves the Camera2D smoothly between hospital floors.
+extends Node
+
+signal room_changed(floor_index: int)
+
+const FLOOR_HEIGHT: float = 720.0
+const CAMERA_TWEEN_DURATION: float = 0.6
+
+var _current_floor: int = 0
+var _camera: Camera2D
+
+
+func initialize(camera: Camera2D) -> void:
+	_camera = camera
+
+
+func go_to_floor(floor_index: int) -> void:
+	if _camera == null or floor_index == _current_floor:
+		return
+	_current_floor = floor_index
+	var target_y: float = floor_index * -FLOOR_HEIGHT
+	var tween: Tween = _camera.create_tween()
+	tween.set_ease(Tween.EASE_IN_OUT)
+	tween.set_trans(Tween.TRANS_SINE)
+	tween.tween_property(_camera, "position:y", target_y, CAMERA_TWEEN_DURATION)
+	room_changed.emit(floor_index)
+
+
+func get_current_floor() -> int:
+	return _current_floor

scripts/systems/settings_menu.gd

@@ -0,0 +1,37 @@
+## SettingsMenu — overlay panel for audio volume and game reset.
+class_name SettingsMenu extends CanvasLayer
+
+
+func _ready() -> void:
+	visible = false
+
+
+func show_menu() -> void:
+	visible = true
+
+
+func hide_menu() -> void:
+	visible = false
+
+
+func _on_music_slider_value_changed(value: float) -> void:
+	AudioManager.set_music_volume(value)
+
+
+func _on_sfx_slider_value_changed(value: float) -> void:
+	AudioManager.set_sfx_volume(value)
+
+
+func _on_reset_button_pressed() -> void:
+	var dialog: ConfirmationDialog = get_node_or_null("Panel/ResetConfirmDialog") as ConfirmationDialog
+	if dialog != null:
+		dialog.popup_centered()
+
+
+func _on_reset_confirmed() -> void:
+	SaveManager.reset_game()
+	get_tree().reload_current_scene()
+
+
+func _on_close_button_pressed() -> void:
+	hide_menu()