Installer: scaffold → uv sync → git init

[ulises-jeremias]

Summary

Orchestrate project creation including optional dependency install and git init.

CNA mapping

CNA: installer.ts (npm/yarn/pnpm/bun install paths).

Acceptance criteria

• Writes files to target directory
• uv sync when install enabled; --no-install skips
• Initializes git repo when appropriate
• --keep-on-failure behavior for partial scaffolds
• Tests with temp dirs

Blocked by

none

Blocks

none

Reference

Parity matrix (workspace): knowledge/create-python-app-parity-matrix.md
Reference repo: https://github.com/Create-Node-App/create-node-app

Parent epic

#4