feat(poc): implement Sprint 1 proof of concept

- project.godot with autoload configuration
- Reception room with placeholder visuals
- Draggable Character with DragDropComponent
- Interactive flower object with bounce animation
- GameState, SaveManager, AudioManager, InputManager autoloads
- HUD with back button and music toggle

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

scenes/main/Main.tscn

@@ -0,0 +1,23 @@
+[gd_scene load_steps=4 format=3 uid="uid://cozypaw_main"]
+
+[ext_resource type="PackedScene" path="res://scenes/rooms/floor0/Reception.tscn" id="1_reception"]
+[ext_resource type="PackedScene" path="res://scenes/characters/Character.tscn" id="2_char"]
+[ext_resource type="PackedScene" path="res://scenes/ui/HUD.tscn" id="3_hud"]
+
+[node name="Main" type="Node2D"]
+
+[node name="Hospital" type="Node2D" parent="."]
+
+[node name="Floor0" type="Node2D" parent="Hospital"]
+
+[node name="Reception" parent="Hospital/Floor0" instance=ExtResource("1_reception")]
+position = Vector2(0, 0)
+
+[node name="Characters" type="Node2D" parent="."]
+
+[node name="Bunny1" parent="Characters" instance=ExtResource("2_char")]
+position = Vector2(300, 400)
+
+[node name="UI" type="CanvasLayer" parent="."]
+
+[node name="HUD" parent="UI" instance=ExtResource("3_hud")]