The route regroups flat props into lines[] and was dropping the role tag,
so the widened feed reached the browser untagged. That is not cosmetic:
on a live prop, PrizePicks prices both sides at even money (+100/+100)
while BetMGM has +450/-750. Rendered side by side without a tag, the
pick'em row reads as a dramatically better price when it is a different
product entirely -- exactly the confusion the three-way split exists to
prevent. Consumers gate on book_role !== 'dfs' before treating a row as a
market price.
The ?book= filter now accepts any DISPLAY book, since shopping a real
book against an exchange is the point of the widening. Grading still only
ever consumes MODEL_BOOKS.
One superseded integration test updated to a stronger pair: an unknown
book still 400s, and a newly-visible one no longer does.
Gates: 4,028 tests / 322 suites green; next build exit 0.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QJs13VsyiSKYQP6rj3NNmc
builtbykev