Add new test file for phase 19 scenery with unique identifier

scripts/terrain/terrain_block.gd

@@ -16,6 +16,8 @@ extends StaticBody2D
 const POLYGON_NODE_NAME := "Polygon2D"
 const OUTLINE_NODE_NAME := "Outline"
 const COLLISION_NODE_NAME := "CollisionPolygon2D"
+const STAGE_SURFACE_RENDERER := preload("res://scripts/stage/scenery/stage_surface_renderer.gd")
+const STAGE_DRAW_ORDER := preload("res://scripts/stage/stage_draw_order.gd")
 
 # ---------------------------------------------------------------------------
 # Exported properties
@@ -55,6 +57,9 @@ const COLLISION_NODE_NAME := "CollisionPolygon2D"
 ## overlaps. Plain var (not inspector-editable).
 var spawn_id: String = ""
 
+## Appearance-only identifier for Ground. Empty preserves the legacy vector fill.
+var finish_id: StringName = &""
+
 # ---------------------------------------------------------------------------
 # Internal node references (built in _ready, @tool-safe)
 # ---------------------------------------------------------------------------
@@ -71,6 +76,15 @@ func _ready() -> void:
 	_ensure_children()
 	_apply_points()
 	_apply_style()
+	if spawn_id == "ground":
+		STAGE_DRAW_ORDER.apply_terrain(self)
+
+
+func set_finish(id: StringName) -> void:
+	finish_id = id if STAGE_SURFACE_RENDERER.is_ground_finish(id) else &""
+	if _polygon != null:
+		_polygon.visible = finish_id.is_empty()
+	queue_redraw()
 
 # ---------------------------------------------------------------------------
 # Internal build / apply
@@ -120,3 +134,14 @@ func _apply_style() -> void:
 	if _outline != null:
 		_outline.default_color = outline_color
 		_outline.width = outline_width
+	if _polygon != null:
+		_polygon.visible = finish_id.is_empty()
+
+
+func _draw() -> void:
+	if spawn_id != "ground" or finish_id.is_empty() or polygon_points.is_empty():
+		return
+	var rect := Rect2(polygon_points[0], Vector2.ZERO)
+	for point: Vector2 in polygon_points:
+		rect = rect.expand(point)
+	STAGE_SURFACE_RENDERER.draw_ground(self, rect, finish_id, fill_color, global_position, global_scale)