[infra] Surface the ASF generative-AI disclosure in the PR template

[weiqingy]

Linked issue: #932

Purpose of change

The ASF generative tooling guidance asks contributors to disclose when generative AI tooling was used to author or co-author a contribution. Our PR template has no field for that, and AGENTS.md does not mention it, so the disclosure is not surfaced anywhere in this project today.

This adds a disclosure section to the PR template, plus one sentence in the AGENTS.md commit and PR guidelines recording the same convention, so that a human contributor and a coding agent reading the repo guide both know to fill it in.

The wording follows the shorter of the two Apache precedents. apache/auron uses a yes/no question with a Generated-by instruction and a link to the ASF guidance. apache/flink uses a longer form with a commented-out trailer plus a project policy line stating that low-effort AI-generated PRs will be closed. I left that policy line out, since it is a project decision rather than a mechanical alignment with the ASF guidance, and seems better raised on its own if maintainers want it.

Two small choices worth a reviewer's eye:

• The Generated-by line is requested in the PR description rather than as a commit message trailer, because this project squash-merges and a per-commit trailer would not reliably survive.
• The heading is phrased as a question to match both Apache precedents, which reads differently from the noun headings used elsewhere in the template. Happy to switch to a noun heading if that consistency matters more.

Tests

Not applicable, documentation only, no logic change.

Ran python3 tools/check-agents-md.py: passes, confirming the AGENTS.md edit leaves the version facts the checker asserts untouched.

Ran ./tools/check-license.sh: RAT checks pass.

API

No. No code or public API change.

Documentation

• doc-included

Was this patch authored or co-authored using generative AI tooling?

• Yes
• No

Generated-by: Claude Code 2.1.220