Fix Open WebUI auth: correct WEBUI_SECRET_KEY and remove Ollama config

- WEBUI_SECRET_KEY now uses dedicated webui-secret-key (not vllm-api-key)
- ExternalSecret updated to fetch webui_secret_key from 1Password
- Remove duplicate OLLAMA_BASE_URLS configuration (vLLM only)

cluster/applications/open-webui/deployment.yaml

@@ -37,7 +37,7 @@ spec:
           valueFrom:
             secretKeyRef:
               name: body-wars-secret
-              key: vllm-api-key
+              key: webui-secret-key
               optional: false
         # Backend configuration for vLLM (OpenAI-compatible, NOT Ollama)
         # OLLAMA_BASE_URLS removed: astro-orbiter runs vLLM, not Ollama