Plan lifecycle: comment-backed reviews, bounded repair loops, implement-start branch

[DocksDocks]

Closes #22

Implements the reviewed plan #22:

• Review records move to issue comments. Each reviewer returns one parser-compatible block; the manager posts it unchanged as one issue comment. Trust requires the comment author to equal the plan's sole assignee; the latest trusted record per review kind wins, with legacy body fallback only when no trusted comment of that kind exists. plan.mjs show surfaces per-kind verdicts; archive requires the latest trusted Code-review: pass.
• Bounded repair loops replace the one-repair dead-end. Both review phases run at most five rounds on fresh inputs; rounds 1-4 repair every named finding; the loop terminates on no progress, a surviving finding, or a round-5 non-pass. Any terminal failure after implementation starts commits and pushes current work before the plan blocks.
• Linked branch at implement start. After plan.mjs status <issue> ongoing, the manager requires a clean worktree, then verifies/creates the issue's linked branch via repository-scoped gh issue develop (--repo, --base <default> --checkout), with failure recovery and no local fallback. Plan-only runs never create a branch.
• Synchronized mirrors. Contract, three skills, four reviewer wrappers, workspace templates, root AGENTS.md, docs/PLAN.md, both READMEs, all three public descriptors, and the verbatim phase tests carry the same wording; the Codex code-reviewer wrapper now inlines the parser-compatible record grammar.

Verification: plan-skill-phases, plan-cli, plugin selftest, and the full scripts/ci.mjs gate all exit 0. Code review: round 1 fixes-required (2 HIGH, both repaired), round 2 pass — records on #22.