feat(fv-ml1): rebalance GPUs 0/1 by usage; contexts to published maximums; gen-small default output cap

Layout: GPU 0 = cyberprev (KV 16 -> 15 GiB, 1.29x), erp-seat (moved from
GPU 1, KV 8.49 -> 5.5 GiB, 1.32x), voices (ctx 8,192 -> 40,960, its native
maximum, KV 6 GiB, 1.07x), coder (moved from GPU 1, ctx 16,384 -> 32,768,
the card maximum, 2.35x), parakeet-nemo. GPU 1 = gen-small (moved from
GPU 0, 5.5 GiB, 1.76x), meromero-rp (22 GiB, 1.32x), intern-decision.

Sizing rule: KV >= 1.25x max context rounded up to 0.5 GiB, checked against
7 days of LiteLLM traffic and the engines' own KV-usage logs. Each card keeps
spare memory for its bursty tenant (parakeet's cap on GPU 0, intern-decision's
32k call on GPU 1). YaRN extensions are not enabled: they do not fit, and the
Qwen cards warn static YaRN degrades short prompts.

gen-small gets --override-generation-config max_new_tokens 32768. It applies
only to requests that omit max_tokens (vLLM get_max_tokens) and answers 9
runaway ~260k-token replies in 7 days; the longest normal reply was 6,357.

Applied with playbooks/fv-ml1-rebalance-20261005.yaml (boot-check guard and
health/KV verification per seat); all nine seats healthy, gateway smoke
tests pass.

scripts/oneoff/wait-healthy.sh

@@ -0,0 +1,16 @@
+#!/bin/bash
+# wait-healthy.sh <container> <max-seconds> — poll docker health every 10 s until it reads
+# healthy; exit 1 at the deadline, or at once if the container exits or starts restarting.
+# "(unhealthy)" alone does not fail it: a seat whose boot outlasts its healthcheck
+# start_period reads unhealthy and then recovers. Prints the elapsed time either way.
+set -u
+c=$1 max=$2 t=0
+while [ "$t" -lt "$max" ]; do
+  st=$(docker ps -a --filter "name=^${c}$" --format '{{.Status}}')
+  case "$st" in
+    *"(healthy)"*) echo "$c healthy after ${t}s"; exit 0 ;;
+    Exited*|Restarting*|Dead*) echo "$c FAILED after ${t}s: $st"; exit 1 ;;
+  esac
+  sleep 10; t=$((t + 10))
+done
+echo "$c NOT healthy after ${max}s: $st"; exit 1