benilla's layer speaks the 1.12 API alone: handlers take this and no arguments, GetBinding answers the 1.12 list, the Key Bindings page captures through its window, /errors chains the error handler, and the host hooks leave the VM (#569)

benilla's layer now uses only the 1.12 API and the 1.12 Lua forms, and the host hooks it used are gone from the VM.

- **The VM calls handlers as 1.12.1 does.** A handler body is compiled as the chunk itself, so `self` in it is an ordinary global (`0x704c70`). A handler is called with no arguments (`0x705199`). The loader reads no `function=` attribute.
- **`GetBinding`/`GetNumBindings` answer the 1.12 list** (`0x4b7f60`): `HEADER_*` section rows, plus every key bound to a command, with no category column. The stock `KeyBindingFrame` now shows its section headers and both key columns.
- **The Key Bindings page captures keys through its own window**, as `Blizzard_BindingUI` does: the frame's `OnKeyDown` for keys, clicks for mouse buttons, and the wheel. It takes the `Benilla` prefix, so loading the stock binding addon no longer breaks it. The UI pointer feed now hands frames mouse buttons 4 and 5.
- **`/errors` keeps its log by chaining the Lua error handler**, and the stock ScriptErrors dialog is unchanged. Load failures that never raise now print one chat line each at world entry.
- **Slash commands:** `/reload` and `/errors` are `SlashCmdList` rows in the layer. `/convertraid` is gone; 1.12.1 has no such command. The dev commands are host rows in dev builds only, so a player build answers them with the unknown-command line once.
- **Naming:** every global the layer defines is `Benilla`-prefixed. `BenillaBindCapture`, `KeyBindings_OnHostKey`, the three script-error globals and `SubmitChatInput` are removed.

Verified:
- New tests for each rule and each removed surface; 16 mutations each fail a test.
- Region dumps of the Options window (general page, Key Bindings, armed) are identical before and after.
- `scripts/gates.sh` and `scripts/smoke.sh` are green.
- A live run bound a key, a Shift chord and the middle button through the page, and opened `/errors`.

Built on macOS; no platform seam touched.

Fixes #539
Fixes #544
Fixes #407
Part of #171

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

crates/benilla-ui/src/script/messageframe/scrolling.rs

@@ -247,26 +247,6 @@ pub(super) fn install(lua: &Lua) -> mlua::Result<()> {
 
     lua.set_named_registry_value(REG_SCROLLINGMESSAGEFRAME_METHODS, m)?;
 
-    // BenillaChatTabPressed(): the chat edit box's OnTabPressed sets a flag for the app's whisper
-    // cycle (`UiScript::take_chat_tab`).
-    lua.globals().set(
-        "BenillaChatTabPressed",
-        lua.create_function(|lua, ()| {
-            let mut model = lua.app_data_mut::<Model>().expect("model app_data");
-            model.chat_tab = true;
-            Ok(())
-        })?,
-    )?;
-    // SubmitChatInput(text): the chat edit box's OnEnterPressed queues the line for the app to
-    // parse as a chat command; an empty line is queued too, and the app takes it as a cancel.
-    lua.globals().set(
-        "SubmitChatInput",
-        lua.create_function(|lua, text: Option<String>| {
-            let mut model = lua.app_data_mut::<Model>().expect("model app_data");
-            model.chat_input.push(text.unwrap_or_default());
-            Ok(())
-        })?,
-    )?;
     Ok(())
 }
 
@@ -699,7 +679,8 @@ mod tests {
              f:SetPoint('BOTTOMLEFT', 0, 0)\n\
              f:SetWidth(430)\n\
              f:SetHeight(120)\n\
-             f:SetScript('OnHyperlinkClick', function(self, link, text, button)\n\
+             f:SetScript('OnHyperlinkClick', function()\n\
+                 local link, text, button = arg1, arg2, arg3\n\
                  CLICKED = link .. '#' .. text .. '#' .. button\n\
              end)",
         )