feat(qwen35-vl): Qwen3.5-9B VL FP8 stack on ana-ml2 GPU1 + LiteLLM entry

Qwen3.5-9B vision-language served FP8 on ana-ml2 GPU1 (co-located with
granite + the embed/rerank/reward trio; GPU0 kept free for hot-loading
large models), :8007, fronted by LiteLLM as qwen3.5-9b-fp8.

Pinned to vllm/vllm-openai nightly@sha256:49211ab2 — :latest (v0.19.1)
quantizes the VL vision tower under fp8 and garbles vision; the nightly
correctly excludes it (LM stays FP8, vision tower BF16). util 0.40
(~38GB) on the shared card (vLLM needs free>=util*total here). Vision
verified end-to-end through the gateway.

stacks/litellm/conf/config.yaml

@@ -30,6 +30,17 @@ model_list:
     model_info:
       mode: chat
 
+  # --- Qwen3.5-9B vision-language (FP8) — vision + chat. vLLM on ana-ml2 GPU 1,
+  #     nightly-pinned (vision-FP8 exclusion fix), :8007. Explicit entry shadows
+  #     the "*" wildcard llama-swap route. ---
+  - model_name: qwen3.5-9b-fp8
+    litellm_params:
+      model: hosted_vllm/qwen3.5-9b-fp8
+      api_base: http://10.250.50.54:8007/v1
+      api_key: os.environ/VLLM_API_KEY
+    model_info:
+      mode: chat
+
   # --- Qwen3 embeddings ---
   - model_name: qwen3-embedding
     litellm_params: