openspec-archive-changelisted

Archive a completed change in the experimental workflow. **Input**: Optionally specify a change name. If omitted, check if it can be inferred from conversation context. If vague or ambiguous you MUST prompt for available changes. **Steps** 1. **If no change name provided, prompt for selection** Run `openspec list --json` to get available changes. Use the **AskUserQuestion tool** to let the user select. Show only active changes (not already archived). Include the schema used for each change if available. **IMPORTANT**: Do NOT guess or auto-select a change. Always let the user choose. 2. **Check artifact completion status** Run `openspec status --change "<name>" --json` to check artifact completion. Parse the JSON to understand: - `schemaName`: The workflow being used - `planningHome`, `changeRoot`, `artifactPaths`, and `actionContext`: path and scope context - `artifacts`: List of artifacts with their status (`done` or other) If status reports `actionContext.mode: "workspace-planning"`, explain that workspace archive is not supported in this slice and STOP. Do not move workspace changes into repo-local archives or edit linked repos. **If any artifacts are not `done`:** - Display warning listing incomplete artifacts - Use **AskUserQuestion tool** to confirm user wants to proceed - Proceed if user confirms 3. **Check task completion status** Read the tasks file (typically `tasks.md`) to check for incomplete tasks. Cou