fix: update service_script path to vllm/server.py

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

model-orchestrator/models.yaml

@@ -6,7 +6,7 @@ models:
   qwen-2.5-7b:
     type: text
     framework: vllm
-    service_script: models/vllm/server.py
+    service_script: vllm/server.py
     port: 8000
     vram_gb: 14
     startup_time_seconds: 120
@@ -16,7 +16,7 @@ models:
   llama-3.1-8b:
     type: text
     framework: vllm
-    service_script: models/vllm/server.py
+    service_script: vllm/server.py
     port: 8001
     vram_gb: 17
     startup_time_seconds: 120