WIP: track creation and deletion both in frontend and backend.

Controls/Track.tscn

@@ -83,12 +83,11 @@ expand_mode = 2
 unique_name_in_owner = true
 custom_minimum_size = Vector2(256, 0)
 layout_mode = 2
-size_flags_horizontal = 0
+size_flags_horizontal = 3
 size_flags_vertical = 4
 theme_override_fonts/font = SubResource("FontVariation_lbdn3")
 placeholder_text = "Empty Track"
 context_menu_enabled = false
-flat = true
 draw_control_chars = true
 caret_blink = true
 script = ExtResource("4_2nwak")