/apply

Implement an approved OpenSpec change and keep tasks in sync.

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**Guardrails**
- Favor straightforward, minimal implementations first and add complexity only when it is requested or clearly required.
- Keep changes tightly scoped to the requested outcome.
- Refer to `openspec/AGENTS.md` (located inside the `openspec/` directory—run `ls openspec` or `openspec update` if you don't see it) if you need additional OpenSpec conventions or clarifications.

**Steps**
Track these steps as TODOs and complete them one by one.
1. Read `changes/<id>/proposal.md`, `design.md` (if present), and `tasks.md` to confirm scope and acceptance criteri...