Resolve a manifest-relative file to the best source this runtime can read: a plain (already seekable) file
if present, else the most-preferred compressed variant that exists AND is decompressible here -- .zst first
when this Node supports zstd, otherwise .br (then .gz). A .zst is never returned on a Node without zstd
(it could not be decompressed), so .br-only bundles read on any Node. Falls back to the plain path.
Resolve a manifest-relative file to the best source this runtime can read: a plain (already seekable) file if present, else the most-preferred compressed variant that exists AND is decompressible here --
.zstfirst when this Node supports zstd, otherwise.br(then.gz). A.zstis never returned on a Node without zstd (it could not be decompressed), so.br-only bundles read on any Node. Falls back to the plain path.