feat: add Azure OpenAI / MS Foundry support for /api/ask

- Add LLM_API_VERSION config for Azure api-version query param
- Detect Azure endpoints and use api-key header instead of Bearer
- Handle base URLs that already include /chat/completions path
- Update .env.example with Azure OpenAI guidance

.env.example

@@ -36,8 +36,12 @@ ALERTS_ENABLED=false
 
 # Optional: LLM configuration for natural language querying (/api/ask)
 # Supports any OpenAI-compatible API (OpenAI, Azure OpenAI, Ollama, etc.)
+# For Azure OpenAI / MS Foundry, set BASE_URL to your deployment endpoint
+# (e.g. https://your-resource.openai.azure.com/openai/deployments/your-deployment)
+# and set API_VERSION to something like 2025-01-01-preview
 LLM_API_KEY=
 LLM_BASE_URL=https://api.openai.com/v1
 LLM_MODEL=gpt-4o-mini
 LLM_MAX_EVENTS=50
 LLM_TIMEOUT_SECONDS=30
+LLM_API_VERSION=