WRITER integration support (#113)

Author: adeweaver

openllmetry/tracing/supported.mdx

@@ -26,6 +26,7 @@ In the meantime, you can still use OpenLLMetry to report the [LLM and vector DB
 | [Replicate](https://replicate.com/)                                                   | ✅     | ⏳         |
 | [together.ai](https://together.ai/)                                                   | ✅     | ⏳         |
 | [HuggingFace Transformers](https://huggingface.co/)                                   | ✅     | ⏳         |
+| [WRITER](https://writer.com/)                                                         | ✅     | ✅         |
 
 ## Vector DBs