Both CodeRabbit findings were right.
1. A HUNG PREPARE COULD BLOCK THE GIG FOREVER.
`await fetch(...)` only rejects on a network ERROR. A server that accepts the
connection and then never answers hangs indefinitely — and the gig would never
start. That makes this optimisation the exact thing the PR promises it can
never be: the reason you cannot play.
The request is now bounded by an AbortController (PREPARE_TIMEOUT_MS, generous
because unpacking a setlist is real work — but a CEILING, not a wait). Past it
we start the gig and let the first play extract lazily, as it always did. The
Play button is restored in a `finally`, so a timeout cannot strand the poster
on "Preparing set…" with Play disabled — which would have been the same bug
wearing a different hat.
2. THE `songs` BODY WAS UNVALIDATED.
A str is iterable: "abc" would have prepared three one-character "songs". And
the endpoint unpacks zips, so an arbitrary caller could ask for unbounded work.
Now list-only, string entries, blanks dropped, capped at MAX_GIG_SONGS.
Tests: the fetch is abortable and the button is re-enabled on EVERY path
including the abort; non-list bodies, non-string/blank entries, and an
oversized setlist. 50 career tests, JS 5/5, eslint clean.
byrongamatos
4825ad2e34