hotfix: implementation in Phase 4 precedes approvals in Phase 5

## Problem The `.claude/skills/hotfix/SKILL.md` workflow performs investigation and implementation in Phase 4, then collects approvals in Phase 5. Since this is an emergency hotfix flow, the sequence allows code changes before lead, QA, and producer sign-off. ## Impact Hotfix workflows are safety-sensitive. Implementing before approval can bypass the audit trail the skill claims to enforce, especially for release branches or urgent production fixes. ## Suggested fix Split the flow into pre-implementation approval and post-implementation validation: 1. Assess severity and draft the proposed fix approach. 2. Ask for approval to implement the hotfix. 3. Implement the minimal fix only after approval. 4. Collect lead, QA, and producer sign-off before deploy or merge.