/specforge:init — bootstrap the lifecycle workspace

Create the committed specforge/ workspace that every other SpecForge command reads and writes. Run this once per project. It is safe to re-run: never overwrite an existing file — only create what is missing and report what already existed.

When to use

• The user wants to start spec-driven development / the SpecForge lifecycle in a repo.
• A session reports "a specforge/ workspace exists but state.md is missing" (repair).

Steps

1. Check whether specforge/ already exists. If it does, only fill in missing files and tell the user what was already present — do not clobber their work.
2. Create this structure at the project root (${CLAUDE_PROJECT_DIR}):