openclaw - 💡(How to fix) Fix pr-release: continue after PR merge and validate release readiness

What to build

Implement the continue phase that validates tracked PRs are merged, records merge commit SHAs, checks reachability from the target branch, detects tag conflicts, and asks the operator how to handle mixed merged/unmerged states.

Acceptance criteria

• Continue uses saved workflow.version unless no version is saved and --version is supplied.
• Each repo verifies PR merged state, merge_commit_sha presence, and target-branch reachability.
• Each repo checks that tag vX.Y.Z does not already exist before release creation.
• Mixed states produce a Lark action choice to continue with merged only or stop.
• Tag conflicts produce skip/stop handling; entering another version is allowed only before draft PRs exist.
• Tests cover merged, unmerged, missing merge commit, unreachable merge commit, and tag conflict cases.

Blocked by

• pr-release: create draft PRs with workspace analysis, secret scanning, and retry