expand-shell

# Expand Shell Expand a shell into a full implementation plan. The shell's Context, Produces, Consumes, Covers, and high-level Implementation Steps are authoritative. Expansion adds a pattern survey, concrete references, and verification, writes the plan to `.turbo/plans/<shell-slug>.md`, and deletes the source shell once the plan is in place. ## Task Tracking Use `TaskCreate` to create a task for each step: 1. Load the shell and verify consumes 2. Run `/survey-patterns` skill (shell-focused) 3. Escalate the shell's open questions 4. Write the plan 5. Verify the plan against the shell 6. Present summary and gate 7. Delete the shell ## Step 1: Load the Shell and Verify Consumes Determine which shell to expand: 1. **Explicit path** — If a file path was passed, use it 2. **Single candidate** — Glob `.turbo/shells/*.md` and filter to shells whose `depends_on` are all satisfied (see satisfaction check below). If exactly one match, use it 3. **Multiple candidates** — If multiple matches, use `AskUserQuestion` to let the user choose 4. **Nothing found** — If no shells exist in `.turbo/shells/`, say so and stop A `depends_on` entry is satisfied when `.turbo/plans/<dep-slug>.md` exists with `status: done` in its frontmatter. Read the shell file. Parse the YAML frontmatter: - **spec** (source spec path) - **depends_on** (list of shell slugs that must already be implemented) Parse these body fields: - **Title** (from the `# Plan:` heading) - **Context** (the why) - **Produce...