- Single-concern renderer (<100 LOC per Constructor Pattern)
- Idempotent — existing files are skipped, not overwritten
- Args: <target> [name] [description]; name defaults to basename,
description defaults to first non-blank line of CLAUDE.md or
README.md, fallback "No description"
- --only <output-path> restricts emission to one file (used by
/new-agent Phase 8 "AGENTS.md only" path)
- Placeholders substituted: PROJECT_NAME, PROJECT_DESCRIPTION,
YEAR, MONTH, DATE
