* feat: track PR lifecycle state per thread for sidebar
Persist a PR's draft/open/merged/closed state on the agent thread and keep
it in sync as PR webhooks fire, so the Agents UI can show per-thread PR
status the way Cursor does. open_pull_request now records the initial
draft/open state and pr_title; thread summaries expose diffStats; and the
PR webhook refreshes pr_state on close/reopen/draft/ready transitions.
Co-authored-by: open-swe[bot] <open-swe@users.noreply.github.com>
* refactor: consolidate PR state mapping into shared derive_pr_state helper
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Co-authored-by: open-swe[bot] <open-swe@users.noreply.github.com>
