Improves tree and ground tile appearance

Refactors tree spawning and rendering:
- Adds seasonal color variations for trees via scripts.
- Introduces `ColorStorage` to manage tree and grass colors
- Removes unused code from tree spawning logic.
- Adjusts ground tile color for better visual appeal.
- Hides debug text on ground tiles.

Entities/GroundTile/GroundTile.tscn

@@ -11,8 +11,7 @@
 viewport_path = NodePath("DebugText/DebugTextViewport")
 
 [sub_resource type="StandardMaterial3D" id="StandardMaterial3D_f37ob"]
-albedo_color = Color(0.133333, 0.576471, 0.47451, 1)
-metallic = 1.0
+albedo_color = Color(0.196078, 0.392157, 0.196078, 1)
 
 [sub_resource type="PlaneMesh" id="PlaneMesh_oqd8f"]
 
@@ -30,6 +29,7 @@ flip_faces = true
 script = ExtResource("1_uwxqs")
 
 [node name="DebugText" type="Node3D" parent="."]
+visible = false
 
 [node name="DebugTextViewport" type="SubViewport" parent="DebugText"]
 size = Vector2i(50, 50)