Switches recipe generation service type from 'cf-text' to 'vllm' so the
coordinator can route to quantized small models (Qwen2.5-3B, Phi-4-mini)
rather than the full text backend. Passes CF_APP_NAME for per-product
VRAM/request analytics in the coordinator dashboard.
- llm_recipe.py: _SERVICE_TYPE = 'vllm'; _MODEL_CANDIDATES list; passes
model_candidates and pipeline= to CFOrchClient.allocate()
- compose.cloud.yml: CF_APP_NAME=kiwi env var for coordinator attribution