style: apply gdformat formatting across the entire project

Auto-format all GDScript files using gdformat from gdtoolkit.
This is a baseline formatting pass to ensure consistent style:

- Normalizes indentation and spacing
- Wraps long lines to 100 characters
- Removes trailing whitespace
- Standardizes blank lines between functions

68 files reformatted, 8 files left unchanged (3rd-party addon files
with parse errors excluded).

addons/terrain_3d/menu/channel_packer_dragdrop.gd

@@ -5,6 +5,7 @@ extends Button
 
 signal dropped
 
+
 func _can_drop_data(p_position, p_data) -> bool:
 	if typeof(p_data) == TYPE_DICTIONARY:
 		if p_data.files.size() == 1:
@@ -13,5 +14,6 @@ func _can_drop_data(p_position, p_data) -> bool:
 					return true
 	return false
 
+
 func _drop_data(p_position, p_data) -> void:
 	dropped.emit(p_data.files[0])