voices-seat: ship lv-bronte (ckpt475) with its failed voice axis on the record

lv-bronte is live on vllm-voices (fv-ml1 GPU0 :8027) alongside voices-base and
lv-yarros. The seat lists all three; container healthy; GPU0 96092 -> 96090 MiB,
so the adapter cost nothing measurable.

IT DID NOT PASS ITS VOICE GATE, and the artifact says so in three places — this
commit, a comment in the compose file, and a README beside the adapter on NFS —
because an adapter found without its provenance will otherwise be read as a pass.

  VOICE       FAIL  +0.193 delta_cb vs base, against a 0.251 measured noise floor
  NOT COPIED  PASS  8-gram hit-rate 0.00, longest 0 - identical to the control
  NO DAMAGE   PASS  ran-on +0.15 against a 0.400 floor

Shipped on three grounds, none of them that the number was nearly good enough:
it is additive (a named LoRA nobody reaches without asking for it), reversible
(one compose line; hot-unload measures 0.003 s), and clean on the axis that
carries actual risk - verbatim regurgitation of the source, on a public-domain
corpus, measured against a positive control that saturates at 160.

The voice result is UNDERPOWERED rather than absent: it closed 48% of the span
from base to the same-author target and beat the control on every individual
seed. The cause is structural - 81 val pairs against Hemingway's 200, from a
678k-word corpus against 994k - and neither more beats nor more seeds fixes it,
because the floor is a range statistic and ranges widen with n.

ckpt475 over ckpt925: indistinguishable on voice (0.017 apart), but ckpt925 has a
verbatim 8-gram hit where this has none, and is 2.7x less stable seed-to-seed
(0.251 vs 0.092) with a degeneracy probe showing no collapse to explain it.

stacks/voices-seat/compose.yaml

@@ -91,6 +91,15 @@ services:
       - "${VOICES_MAX_LORA_RANK:-32}"
       - --lora-modules
       - lv-yarros=/adapters/lv-yarros-4b-v1
+      # ⚠ lv-bronte did NOT pass its voice gate: +0.193 delta_cb toward held-out
+      # Brontë against a 0.251 measured noise floor. Shipped anyway because it is
+      # additive, reversible, and clean on the safety axis (8-gram overlap 0.00,
+      # identical to the never-saw-it control). The effect is underpowered, not
+      # absent — it closed 48% of the achievable span and beat base on every seed.
+      # Do not cite it as evidence pair-SFT works for this author.
+      # See /adapters/lv-bronte-4b-v1/README.md and
+      # persistent-memory.d/2026-09-17-lv-bronte-gate.md
+      - lv-bronte=/adapters/lv-bronte-4b-v1
     deploy:
       resources:
         reservations: