Implements procedural ground tile generation

Adds procedural ground tile generation with chunking for improved performance.

Includes:
- Ground tile entity with debug text and cell information
- Grass and tree placement based on cell data
- Ground shader for visual representation
- Chunk loading and unloading system based on player position

Entities/Player/scripts/player.gd

@@ -9,7 +9,8 @@ func _ready() -> void:
 	position = Vector3.ZERO
 
 func _physics_process(delta):
-	%MultiMesh3D.set("instance_shader_parameters/player_position", position)
+	RenderingServer.global_shader_parameter_set("player_position", position)
+
 	%TileGround.update_chunks(position)
 
 	# We create a local variable to store the input direction.