The score_slider synthesized a symmetric +/-liked pair, so its axis was
"liked vs anti-liked mirror" — meaningless as an away-from-bad signal. When
3+ disliked/awful gens have populated the existing bad_dir slot in the same
taste store, build the slider's minus pole from that real disliked direction
instead. The (eps_+ - eps_-) axis becomes good-vs-bad, actively steering the
noise prediction away from the conditioning region that produced rated-bad
gens. Falls back to the symmetric mirror when no bad_dir exists.
Reuses existing plumbing: bad_dir is already accumulated identically to
liked_dir (running-averaged unit-norm delta from session mean). Generalized
the direction loader to _load_taste_direction(slot); load + pass bad_dir at
the call site; log/run-mechanism note which pole is active.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>