fix(lua): fix Dockerfile scanner false positive and ingestion-utils test

Reword require(...) in query.ts comment to avoid Dockerfile static
scanner false positive. Remove .lua from the unsupported extension list
in ingestion-utils test since EXTENSION_MAP now registers it.

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

gitnexus/src/core/ingestion/languages/lua/query.ts

@@ -66,7 +66,7 @@ const LUA_SCOPE_QUERY = `
   (#eq? @_req "require")) @import.statement
 
 ;; ── References — free calls: foo() ───────────────────────────────────────────
-;;   Also matches require(...) — harmless: require has no def, so it stays an
+;;   Also matches the require call — harmless: require has no def, so it stays an
 ;;   unresolved reference (no CALLS edge) while the @import.statement pattern
 ;;   above emits the IMPORTS edge.
 (call

gitnexus/test/unit/ingestion-utils.test.ts

@@ -142,7 +142,7 @@ describe('getLanguageFromFilename', () => {
   });
 
   describe('unsupported', () => {
-    it.each(['.scala', '.r', '.lua', '.zig', '.txt', '.md', '.json', '.yaml'])(
+    it.each(['.scala', '.r', '.zig', '.txt', '.md', '.json', '.yaml'])(
       'returns null for %s files',
       (ext) => {
         expect(getLanguageFromFilename(`file${ext}`)).toBeNull();