add-plan-todos（添加计划待办事项）

Add and refine todos in the current plan before and during implementation.

Workflow

1. Read the user request and current plan state.
2. Add missing todos so every phase is represented:

- context gathering - implementation - validation/testing - final reporting

1. Split broad work into atomic todos that describe one action each.
2. Add guardrail todos for risky steps (assumptions, dependencies, migrations, irreversible actions).
3. Add explicit verification todos with concrete checks or commands.
4. Reorder todos so dependencies come first and only one todo is in_progress.
5. Mark covered todos completed and keep remaining work pending.

Quality Bar

• Make each todo specific, testable, and observable.
• Avoid combined todos like "implement and test" in one step.
• Prefer adding one extra todo over leaving ambiguity.
• Update the plan whenever scope, constraints, or findings change.