Revise the covers spec: both links given directly, static page served by a
Cloudflare Worker plus a userscript on one pure core, Bun instead of Node,
and R2 rehosting with a 30-day expiry. Move the spec to docs/specs/, merge
HANDOVER.md into docs/DECISIONS.md, the spec and docs/TODO.md, and add
AGENTS.md, pointer files, PERMISSIONS.md and agent permission configs.
Co-Authored-By: Claude Opus 5.5 <[email protected]>