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/cursor/drag.rs

@@ -108,13 +108,13 @@ mod tests {
             local a = CreateFrame("Frame", "A")
             a:SetPoint("BOTTOMLEFT", 0, 0); a:SetWidth(400); a:SetHeight(600); a:EnableMouse(true)
             a:RegisterForDrag("LeftButton")
-            a:SetScript("OnDragStart", function(self, button) drag_starts = drag_starts + 1; drag_button = button end)
-            a:SetScript("OnDragStop", function(self) drag_stops = drag_stops + 1 end)
-            a:SetScript("OnClick", function(self) click_a = click_a + 1 end)
+            a:SetScript("OnDragStart", function() local self, button = this, arg1 drag_starts = drag_starts + 1; drag_button = button end)
+            a:SetScript("OnDragStop", function() local self = this drag_stops = drag_stops + 1 end)
+            a:SetScript("OnClick", function() local self = this click_a = click_a + 1 end)
             local b = CreateFrame("Frame", "B")
             b:SetPoint("BOTTOMLEFT", 400, 0); b:SetWidth(400); b:SetHeight(600); b:EnableMouse(true)
-            b:SetScript("OnReceiveDrag", function(self) receives = receives + 1 end)
-            b:SetScript("OnClick", function(self) click_b = click_b + 1 end)
+            b:SetScript("OnReceiveDrag", function() local self = this receives = receives + 1 end)
+            b:SetScript("OnClick", function() local self = this click_b = click_b + 1 end)
             "#,
         )
         .unwrap();
@@ -170,7 +170,7 @@ mod tests {
             local a = CreateFrame("Frame", "A")
             a:SetPoint("BOTTOMLEFT", 0, 0); a:SetWidth(400); a:SetHeight(600); a:EnableMouse(true)
             a:RegisterForDrag("LeftButton")
-            a:SetScript("OnClick", function(self) clicks = clicks + 1 end)
+            a:SetScript("OnClick", function() local self = this clicks = clicks + 1 end)
             "#,
         )
         .unwrap();
@@ -192,7 +192,7 @@ mod tests {
             local a = CreateFrame("Frame", "A")
             a:SetPoint("BOTTOMLEFT", 0, 0); a:SetWidth(400); a:SetHeight(600); a:EnableMouse(true)
             a:RegisterForDrag("LeftButton")
-            a:SetScript("OnClick", function(self) clicks = clicks + 1 end)
+            a:SetScript("OnClick", function() local self = this clicks = clicks + 1 end)
             "#,
         )
         .unwrap();
@@ -271,7 +271,7 @@ mod tests {
             heard, name, quality = 0, nil, nil
             local f = CreateFrame("Frame", "Listener")
             f:RegisterEvent("DELETE_ITEM_CONFIRM")
-            f:SetScript("OnEvent", function(self, event, n, q) heard = heard + 1; name = n; quality = q end)
+            f:SetScript("OnEvent", function() local self, event, n, q = this, event, arg1, arg2 heard = heard + 1; name = n; quality = q end)
             "#,
         )
         .unwrap();