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/message.tscn

@@ -0,0 +1,18 @@
+[gd_scene format=3]
+
+[ext_resource type="Script" path="res://mods/ui_base/src/Messages/UiMessage.cs" id="1_msg"]
+
+[node name="Message" type="Control" node_paths=PackedStringArray("textField")]
+layout_mode = 3
+anchors_preset = 0
+script = ExtResource("1_msg")
+textField = NodePath("Label")
+
+[node name="Label" type="Label" parent="."]
+layout_mode = 0
+offset_left = 0.0
+offset_top = 0.0
+offset_right = 0.0
+offset_bottom = 0.0
+theme_override_colors/font_color = Color(0.909804, 0.898039, 0.870588, 1)
+text = ""