Add language identifier to AGENTS.md code block

Fixes markdownlint MD040 warning.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: 2 people

AGENTS.md

@@ -12,7 +12,7 @@ License: MIT
 
 Monorepo with Bun workspaces.
 
-```
+```text
 packages/          # 26 modular @tko/* packages (all TypeScript)
 builds/            # 2 bundled distributions (knockout, reference)
 tools/             # Shared build script (build.ts)