Embassy v4.5.2

Embassy 4.5.2 — the demo, designed

No code change from 4.5.1. The video at the top of both READMEs is remade design-first: a light palette around the mark's amber, the recorded terminals set into the page as dispatch cards marked RECORDED, an illustrated SSH scene marked as such, and a new live exchange — a Claude Code session asks a Codex agent to review a login-flow change, the agent reads the real diff and names the risk, and the reply arrives back in Claude with both receipts settled. Nothing on screen is invented. The same file is attached to this release as embassy-demo.mp4; the Remotion project under demo/ is updated and stays out of the package.

Upgrading — nothing to do.

Tested with offline suite 414/414 on Node 22 (macOS and Ubuntu).