Fix Open WebUI connectivity to astro-orbiter

- Add ExternalName Service for astro-orbiter (10.1.71.130:8000)
- Remove Ollama-specific configuration (OLLAMA_BASE_URLS)
- Keep only OpenAI-compatible configuration (OPENAI_BASE_URL)

Fixes: Open WebUI pod was attempting to use Ollama endpoints (/api/tags)
against vLLM which only supports OpenAI-compatible API (/v1/models).
Pod now reaches astro-orbiter via Kubernetes Service DNS name.

Resolves: HTTP 404 errors from Upstream ollama request failed

cluster/applications/open-webui/deployment.yaml

@@ -39,9 +39,8 @@ spec:
               name: body-wars-secret
               key: vllm-api-key
               optional: false
-        # Backend configuration for vLLM
-        - name: OLLAMA_BASE_URLS
-          value: "http://astro-orbiter:8000"
+        # Backend configuration for vLLM (OpenAI-compatible, NOT Ollama)
+        # OLLAMA_BASE_URLS removed: astro-orbiter runs vLLM, not Ollama
         - name: OPENAI_BASE_URL
           value: "http://astro-orbiter:8000/v1"
         - name: OPENAI_API_KEY