feat: show Ollama plugin badge and available LLM models on marketplace cards

Backend:
- Add attributes field to MarketplaceOfferView schema
- Include attributes in _to_offer_view() response

Frontend:
- Add attributes type with Ollama fields to OfferRecord
- Show purple 'Ollama' plugin badge on cards with models
- Display available LLM model tags (gemma3, deepseek-r1, etc.)
- Add plugin-badge and model-tag CSS styles

apps/coordinator-api/src/app/schemas.py

@@ -196,6 +196,7 @@ class MarketplaceOfferView(BaseModel):
     cuda_version: Optional[str] = None
     price_per_hour: Optional[float] = None
     region: Optional[str] = None
+    attributes: Optional[dict] = None
 
 
 class MarketplaceStatsView(BaseModel):

apps/coordinator-api/src/app/services/marketplace.py

@@ -87,4 +87,5 @@ class MarketplaceService:
             cuda_version=offer.cuda_version,
             price_per_hour=offer.price_per_hour,
             region=offer.region,
+            attributes=offer.attributes,
         )