[25.12] Sync .github folder with master branch

[BKPepe]

This PR adds formalities.json, so bot will use it instead of using bot's default, which might be strict for main repo. While at it backport commits related to Claude.

[openwrt]

Formality Check: Failed

We completed the verification flow. Please review the formatting overview logs below.

🛑 CRITICAL ERRORS

Commit 61f9378 - github: LLM-review: stop reviewing new PRs automatically:

• Commit subject must start with a lower-case word after the prefix

Commit 99a10e8 - github: LLM-review: run the digest twice a day:

• Commit subject must start with a lower-case word after the prefix

Commit 87c745f - CI: migrate to webhook bot and simplify labeler:

• Line 3 in commit body exceeds max width (140/100 chars)
• Line 5 in commit body exceeds max width (208/100 chars)
• Line 8 in commit body exceeds max width (118/100 chars)
• Line 9 in commit body exceeds max width (104/100 chars)
• Line 10 in commit body exceeds max width (114/100 chars)
• Line 13 in commit body exceeds max width (104/100 chars)

Commit 557a8e1 - CI: remove labeler workflow and enable webhook-based labeling:

• Line 3 in commit body exceeds max width (254/100 chars)

Tip

Do not close this pull request to make corrections. Instead, modify your existing commits (e.g. git commit --amend) and update the branch using git push --force-with-lease --force-if-includes. The checks will re-run automatically.

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_{Something broken? Consider reporting an issue.
Running version 4ca9b59 deployed on 2026-07-20 07:30:15 CEST}