pr-retrospectivelisted

# PR Retrospective ## Project wiring (the parent library's instantiation; adopters substitute their own) Portable procedure, concrete names. In the parent GRC library this skill runs with: - Improvement-log register: `.working/improvement-log.md` (the append-only per-PR retrospective register this skill writes; one row per merged PR). - Worker-hallucination metrics register: the worker-hallucination-metrics ledger in the consuming project's working state (the apply-time worker-correction log consumed as retrospective input). - Worker-brief template: `.working/worker-brief-template.md` (the worker-side guard-rail carrier that pattern findings may extend). - Sibling per-PR validation-sweep history register: `.working/validate-pr/history.md` (whose reverse-chronological row convention the improvement-log register mirrors). - The parent register's concrete table header keeps its original columns (`Date | PR | FR closed | ...`); the generic output format below names that column `Backlog item closed`, and the parent's paired slash-command stub carries the concrete form. An adopting project maps each bullet to its own records; the procedure below refers to them generically. ## Overview After each successful merge and `/validate-pr` cycle, conduct a brief retrospective on the PR's process. The retrospective is **light-touch** (one entry per PR, 3-5 sentences) rather than a deep analysis; the value emerges over time as patterns surface across many entries. The output is the **