Texture and FontString stop answering each other's methods

- the one shared region table splits into the client's own maps: a Texture no longer answers SetText, a FontString no longer answers SetTexture, and feature-detecting addons see the true surface
- CreateTitleRegion lands whole — object and drag — so an options window that is its own drag handle actually moves
- font-object names resolve whatever their case, and the CursorUpdate/CursorOnUpdate pair arrives for the container-item templates
- GetStringHeight is pruned (1.12 has no such method) and SetPortraitToTexture moves to the global it really is

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

crates/benilla-app/src/ui_script/quest_tests.rs

@@ -627,7 +627,7 @@ fn greeting_panel_title_rows_grow_to_their_wrapped_titles() {
     let row = |i: u32| -> (f32, f32, f32) {
         s.eval::<(f32, f32, f32)>(&format!(
             "local b = getglobal('QuestTitleButton{i}')\n\
-             return b:GetTop(), b:GetBottom(), b:GetFontString():GetStringHeight()"
+             return b:GetTop(), b:GetBottom(), b:GetFontString():GetHeight()"
         ))
         .unwrap()
     };