Add troubleshooting section for prompt failures in AI Assistant documentation (#3073)

Author: mcasperson

src/pages/docs/octopus-ai/assistant/index.mdx

@@ -114,3 +114,9 @@ A: No, Octopus AI Assistant is self-contained and only requires access to an Oct
 **Q: Is Octopus AI Assistant a supported service?**
 
 A: Yes. Reach out to the [Octopus Support team](https://octopus.com/support) for any issues or questions.
+
+## Troubleshooting
+
+### Prompts fail immediately without appearing to send
+
+The extension may be set to restrict site access. In Chrome, click the kebab menu, select `Extensions` -> `Manage Extensions`. Enable `Developer mode` using the toggle in the top right. Find `Octopus AI Assistant` and click `Details`. Under `Site access`, ensure `On all sites` is selected.