Mod naming rule and engine UI in engine mods

Mods are renamed by role (shell2d_base, menu_base, ui_base, live2d_base,
editor_tools, cthangover_story, cthangover_murakami, cthangover_party) and
every reference follows. Engine UI prefabs (dialog, answers, message, game
menu, inventory, map, skills) and their panel entries moved out of the story
mod into the subsystem mods; the card_novel and vn_starter_novel collections
are removed.

scenes/ui/dialog_canvas.tscn

@@ -0,0 +1,12 @@
+[gd_scene format=3]
+
+[ext_resource type="Script" path="res://mods/dialog_base/src/UI/Dialog/DialogCanvas.cs" id="1_canvas"]
+
+[node name="DialogCanvas" type="Control"]
+layout_mode = 3
+anchors_preset = 15
+anchor_right = 1.0
+anchor_bottom = 1.0
+grow_horizontal = 2
+grow_vertical = 2
+script = ExtResource("1_canvas")