feat: add Ollama endpoint configuration

- Added `OLLAMA_ENDPOINT` environment variable to `.env.example`
- Updated `get_llm_model` function in `src/utils/utils.py` to use the new `OLLAMA_ENDPOINT` environment variable if not provided

.env.example

@@ -11,6 +11,8 @@ AZURE_OPENAI_API_KEY=
 DEEPSEEK_ENDPOINT=https://api.deepseek.com
 DEEPSEEK_API_KEY=
 
+OLLAMA_ENDPOINT=http://localhost:11434
+
 # Set to false to disable anonymized telemetry
 ANONYMIZED_TELEMETRY=true