<objective> Archive phase directories from completed milestones into .planning/milestones/v{X.Y}-phases/.
Use when .planning/phases/ has accumulated directories from past milestones. </objective>
<execution_context> @${CLAUDE_PLUGIN_ROOT}/workflows/cleanup.md </execution_context>
<process> Follow the cleanup workflow at @${CLAUDE_PLUGIN_ROOT}/workflows/cleanup.md. Identify completed milestones, show a dry-run summary, and archive on confirmation. </process>