Allow joined private Slack channel prefixes

[f-trycua]

What changed

• add exact-ID-or-private-prefix channel admission
• require Slack-confirmed private channel membership and fail closed on metadata errors
• preserve mention gating and document YAML/environment configuration

Verification

• 62 focused Slack tests passed
• 448 Slack Python tests passed
• focused Ruff checks and git diff --check passed

[github-actions]

૮ >ﻌ< ა ci review

_{ran on d7dc5b7 — feat(slack): allow joined private channel prefixes}

⚠️ Warnings

OSV vulnerability scan · View job

5 known vulnerabilities found in pinned dependencies.

• CVE-2026-67213 in package-lock.json
• CVE-2026-67213 in website/package-lock.json
• CVE-2026-70608 in package-lock.json
• CVE-2026-56876 in package-lock.json
• CVE-2026-70606 in package-lock.json

How to fix:

Review the findings in the Security tab. Update the affected dependencies if a patched version is available.

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debug info

CI timings

CI timings · View report · View job

Wall time 2m58s vs 3m15s (-8.7%). 8 job(s) slower, 13 faster, 4 unchanged.

• Docs Site / docs-site-checks: -36.0s
• Python tests / Run tests slice 3/12: -27.0s
• Python tests / Run tests slice 11/12: +26.0s
• Python tests / Run tests slice 7/12: -11.0s
• Python tests / Run tests slice 12/12: +7.0s