vllm: rename stack from vllm-qwen3 → vllm + add Skywork reward classifier

Two related changes shipped together. The stack rename is independent
but adding `vllm-reward` to the existing `vllm-qwen3` would have made
that name actively misleading.

**Rename:** `stacks/vllm-qwen3/ → stacks/vllm/`. Updated all in-repo
references (README.md root, servers/ana-ml2/, stacks/llama-swap/,
configs/restic/ana-ml2/, docs/runbooks/disaster-recovery.md). Two
intentional history mentions retained (servers/ana-ml2 + stacks/vllm
README).

**Add `vllm-reward` service:** serves Skywork-Reward-V2-Llama-3.1-8B-AWQ
on port 8003. The AWQ output is a locally-quantized model (not from HF),
so bind-mounts `/tank/aimodels/llm:/local-models:ro` rather than the
shared HF cache. Model config.json declares LlamaForSequenceClassification
which vLLM's pooling runner picks up automatically — produces a single
reward score per input via /classify.

**Flag note:** the user's spec listed `--task classify`, but vLLM 0.19.1
deprecated --task in favor of --runner pooling (model architecture in
config.json drives the classification head). Compose uses --runner
pooling with a comment explaining the substitution.

**GPU memory:** no rebalance needed — production had already tuned
EMBED/RERANK down from 0.40 to 0.20 each (canonical .env.example now
matches reality). Adding REWARD at 0.30 totals 0.70, leaving ~14 GB
headroom on the 48 GB Ada.

**Server-side:** brought existing vllm-qwen3 down, mv'd
/opt/docker/compose/vllm-qwen3 → /opt/docker/compose/vllm, appended
REWARD_* lines to existing .env (preserving API_KEY/HF_TOKEN), deployed
new compose via scripts/deploy-stack.sh, brought all 3 services up.

**Smoke tests:**
- /health on 8001/8002/8003 → 200
- /v1/models on 8003 → lists Skywork/Skywork-Reward-V2-Llama-3.1-8B-AWQ
  with max_model_len 16384
- /classify with a sample conversation → returns LABEL_0 with prob 0.9999
  (single-output regression-style reward score, expected shape for a
  reward model)

configs/restic/ana-ml2/README.md

@@ -29,7 +29,7 @@ pre-backup DB hook is required. Contrast with `configs/restic/ana-docker/`
 where synapse/seafile/vaultwarden DB dumps run first.
 
 - `llama-swap` — GGUF swapper (llama.cpp)
-- `vllm-qwen3` — embedding + rerank
+- `vllm` — embedding + rerank + reward classifier
 - `comfyui`, `kokoro`, `parakeet`, `vibevoice`
 - `beszel-agent-ana`, `dozzle-agent-ana`, `dockge`
 

configs/restic/ana-ml2/profiles.yaml

@@ -12,7 +12,7 @@
 #     caches, llama.cpp GGUFs, ComfyUI models, etc.) — all regenerable
 #     from upstream. Backing them up would blow the repo size budget.
 #   - No DB dumps needed. None of the stacks on this host (llama-swap,
-#     vllm-qwen3, comfyui, kokoro, parakeet, vibevoice, beszel-agent,
+#     vllm, comfyui, kokoro, parakeet, vibevoice, beszel-agent,
 #     dozzle-agent, dockge) store relational data.
 
 version: "1"