[NicolasDorier]

Summary

• Remove fork-local AGENTS.md and the update-btcpay-cln skill after migrating their procedures to the shared maintenance repository.
• Add a short README link so maintainers and agents can discover the new entry point.
• Keep product patches, Dockerfiles, entrypoint and image publishing CI unchanged.

Dependency and related work

Merge btcpayserver/image-maintenance#1 first so the master links resolve. The centralized procedure incorporates applicable corrections from #5, including both downstream integration gates, per-platform source verification, generated Docker documentation and publication-aware recovery. This PR does not modify or close #5 or its branch.

Historical published tags remain unchanged. Future linear patch replay should carry functional patches, not the old instruction-only commit.

Validation

• Pass git diff --check for this documentation-only change.
• Preserve all fork build, runtime and CI files unchanged.
• Validate destination documentation links and helpers in the parent repository tests.

No release branch rewrite, new image publication, downstream bump or live deployment was performed. The existing instructions PR #5 records unrelated ShellCheck failures in the unchanged entrypoint; this migration does not attempt to fix those.

Changelog-None

[NicolasDorier]

Current-head CI reached source checks after the changelog exemption was added, then failed on the same existing entrypoint ShellCheck findings documented in #5:

• tools/docker-entrypoint.sh:93:12 — SC1090
• tools/docker-entrypoint.sh:114:16 — SC1090

Run: https://github.com/btcpayserver/lightning/actions/runs/41990684401

The entrypoint is unchanged by this documentation migration. I have not weakened CI or added unrelated runtime changes. The PR remains draft pending image-maintenance#1 and maintainer review of this existing CI blocker.

[NicolasDorier]

Squashed the cleanup to one commit and verified its final tree is unchanged. The shared repository is merged in btcpayserver/image-maintenance#1. Current CI run https://github.com/btcpayserver/lightning/actions/runs/42011335885 fails only on the same pre-existing SC1090 findings in unchanged tools/docker-entrypoint.sh lines 93 and 114. Nicolas explicitly requested merging the related PRs; proceeding with this documentation-only cleanup without changing runtime code or disabling checks.