Add CI review lane with persistent findings ledger

[VincentShipsIt]

Context

Tools like roborev and no-mistakes validate the same direction for ShipCode: AI-generated work needs a durable review/checks layer, not just transient verifier text. For ShipCode, the right product shape is a GitHub/CI review lane attached to PRs and pipeline runs.

This should behave like a first-class CI review system: review generated commits/PR diffs, persist findings, expose unresolved items in the app, and feed structured findings back into execution/refine retries.

Goal

Add a CI/PR review lane that turns reviewer/verifier output into persistent findings linked to a thread, plan, execution attempt, commit/sha, and PR/check run.

Requirements

• Persist review findings as structured records instead of only storing latest phase output.
• Link each finding to enough source-of-truth context: project, thread, plan/review round, execution attempt, worktree path/branch, commit SHA when available, PR number when available, phase, severity, status, and source agent/model.
• Surface an open findings queue in the desktop app so unresolved findings do not disappear after retries.
• Support finding lifecycle states: open, fixed, ignored, superseded, and closed.
• When verification/review fails with structured findings, route retry back through execution/refine with the findings included in the executor prompt.
• Add a GitHub/CI integration path that can publish review status to the PR as a check/status/comment once a PR exists.
• Keep the implementation path-as-truth for worktrees: always use persisted thread/worktree paths, never recompute cleanup paths from thread IDs.
• Clamp any IPC/reviewer/CI error messages before they reach the renderer.

Acceptance Criteria

• A failed structured review or verification creates durable finding records.
• Retrying from a structured failure resumes execution/refine with those findings, not another blind verify run.
• The app can show current open findings for a thread/PR after the original phase output has changed.
• A later successful fix can mark prior findings fixed or superseded without deleting history.
• PR/check publishing is optional/configurable and does not block local pipeline execution when GitHub integration is unavailable.
• Tests cover finding persistence, retry routing from structured failures, lifecycle transitions, and renderer-safe error clamping.

Notes

Competitive reference points:

• roborev: persistent review ledger, per-commit reviews, open findings queue, refine loop, workflow-specific models.
• no-mistakes: push/PR gate, disposable worktrees, fixed validation sequence, CI babysitting.

ShipCode should not copy their CLI/TUI product shape. The useful piece is the durable CI-review layer inside ShipCode's issue-to-PR pipeline.