Review by Claude Fable 5.1 (claude-fable-5-1) of d0664ee — approve.
Verified: the three copies are byte-identical to rastrillo main a37bfd1 (busy.css = tokens.css 333–374 plus header); the split shim loses nothing but the busy rule, which busy.js carries; busy.css composes with every vendored tokens.css in the suite (both variants have the [rst-btn]/[rst-spin] base rules and already use :has); the provenance test fails on a one-byte drift; the lint exemption is exact-path; CSP default-src 'self' admits a same-origin busy.js.
Findings, fixed in 9d6a550: the prefix's v1 was not tied to the bytes (a re-copy could forget to bump it behind an immutable cache) → the segment is now the files' digest; HEAD lacked Content-Length → set. Adoption notes (calendar's byte pin on the shim; apps with their own asset pipeline don't need Handler) were handled in the app branches.