Add a License section and status badges to the README

[nojibe]

Problem

The LICENSE file is MIT, but the README (~40KB) never states the license, and there are no status badges. For an OSS project this hurts discoverability and trust — visitors can't see at a glance the license, CI status, or contribution welcome.

Proposed change

• Add a License section near the end of the README pointing to LICENSE (MIT © 2025 James Padolsey / contributors)
• Add badges at the top: License (MIT), CI status (once the CI workflow lands), and optionally a "PRs welcome" / contributing link
• Link CONTRIBUTING.md, CODE_OF_CONDUCT.md, and SECURITY.md from the README

Acceptance criteria

• README has a clearly visible License section
• License + CI badges render at the top of the README
• Community docs (contributing / conduct / security) are linked