Summary

Establish a documented policy for closing pull requests that have gone inactive. The current governance docs cover decision-making tiers and review windows but do not define what happens when a PR stalls with no author response.

Motivation

Abandoned PRs occupy reviewer bandwidth, block branch cleanup, and can conflict with newer work. A published policy protects contributor expectations and gives maintainers a transparent mechanism for closing stale PRs without friction.

Proposed Policy Elements

• Author response window: PRs with pending review feedback that receive no author response for 14 days receive a reminder comment.
• Closure threshold: PRs with no activity for 30 days after the reminder are closed with a closed-stale label.
• Draft PRs: Draft PRs with no activity for 60 days are subject to the same closure flow.
• Exemptions: PRs linked to active milestone items or labeled do-not-close are exempt.
• Reopening: Authors can reopen and update their branch at any time; reopening resets the inactivity clock.

Acceptance Criteria

• GOVERNANCE.md or CONTRIBUTING.md contains a new section defining the inactivity closure policy for pull requests.
• The policy distinguishes between PRs awaiting author response and PRs awaiting reviewer response (inactivity clock applies to author-side inactivity only).
• Policy parameters (reminder period, closure threshold, exemptions) are explicit and unambiguous.

Implementation Notes

• This issue covers documentation only. Automation (stale bot, scheduled workflows) is a separate effort that should reference this policy once merged.
• Consider placing PR-specific policy in CONTRIBUTING.md alongside the existing PR guidance, with a cross-reference from GOVERNANCE.md.
• The inactivity clock should be author-side only — a PR should not be closed for stale maintainer review.