fix(hljs): import highlight.js types explicitly for v11

highlight.js v11 ships its type defs inside `declare module
'highlight.js'` instead of as global ambient types, so the v10-era
`/// <reference types="highlight.js" />` stopped exposing HLJSApi /
Language / Mode (TS2304). Replace it with an `import type`.

Signed-off-by: Simon Davies <simongdavies@users.noreply.github.com>

Author: simongdavies

src/agent/hljs-kql.ts

@@ -8,7 +8,12 @@
 //
 // ─────────────────────────────────────────────────────────────────────
 
-/// <reference types="highlight.js" />
+// highlight.js v11 ships its type definitions inside `declare module
+// 'highlight.js'` rather than as global ambient types, so the v10-era
+// `/// <reference types="highlight.js" />` no longer exposes `HLJSApi`,
+// `Language` or `Mode`. Import them explicitly instead (`import type` is
+// erased at compile time, so there is no runtime dependency change).
+import type { HLJSApi, Language, Mode } from "highlight.js";
 
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