_record_contributions now normalizes each source's top-N to [0,1] by its own
top score before summing across sources. ListenBrainz co-occurrence counts
(thousands) no longer drown Last.fm's 0–1 match scores, so a small-scale
source contributes real ranking signal instead of only adding candidates.
Discovery score assertions updated to the normalized scale (single-candidate
fakes normalize to 1.0); added a cross-source test showing a small-scale
source's candidate ranks equal to a large-scale one. min_score is now on the
[0, n_sources] scale (default 0.0 → unaffected). worker 231 tests.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Jonathan
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