Soak: signed URLs serve 206 through their parsed exp (+14.96 min batch)
and return 403 with an Akamai HTML error page by +17.5 min. Resolver
must refresh ahead of exp, treat 403 as stale-lease (re-mint by track
id), and validate audio/mpeg before decoding. ID3v2.4 empty shell
verified byte-identical on 7/7 extra samples; 18- and 26-minute tracks
carry the same uniform 30 s / 480 KB / 128 kbps preview artifact.
The previous .git directory was found gutted (only info/ remained), so
history is unrecoverable locally. This commit restores version control
with the tree exactly as it stands: the working app, the preview-tracks
launcher on the artist hero, the scrollable-track-previews design bundle
(docs + approved mockups), and the Phase 0 validation artifacts.