feat: add CLIP embedding service sidecar for GPU machine

FastAPI service that loads ViT-L-14 model and exposes /embed,
/similarity, and /batch-similarity endpoints. Runs on RTX 3090
with NVIDIA GPU reservation. Includes 9 cosine similarity tests.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

clip-service/app/requirements.txt

@@ -0,0 +1,7 @@
+fastapi>=0.115.0
+uvicorn[standard]>=0.34.0
+open-clip-torch>=2.29.0
+torch>=2.5.0
+Pillow>=10.0.0
+numpy>=1.26.0
+python-multipart>=0.0.18