docs: AGENTS.md update recovered from a worktree

[oratis]

Recovered from an uncommitted worktree on main during a cross-project sweep. Single file: AGENTS.md.

⚠️ Opened so the change isn't lost, not because it was reviewed.

🤖 Generated with Claude Code

[oratis]

Reviewed — closing without merging.

The entire diff is two blank lines added inside an HTML comment block:

 <!-- BEGIN:nextjs-agent-rules -->
+
 # This is NOT the Next.js you know
 ...
+
 <!-- END:nextjs-agent-rules -->

That's a formatter/editor artifact, not work someone did. Nothing is lost by dropping it — the sweep that opened this PR was deliberately indiscriminate (its job was to surface uncommitted state, not to judge it), and this is one of the cases where the judgement is "no".