fix: add null check to inline controller on change

[abeatrix]

fix: add null checks before accessing editor properties

The code to track copy action from inline chat was accessing properties on the editor object without first checking if it was null. This adds null checks before accessing the document and uri properties to avoid potential null reference errors.

This should fix an issue that I run into where VS Code is complaining about Cannot read properties of undefined (reading 'scheme') when I try to start a new chat session:

Test plan

I'm not sure what the exact steps to reproduce the issue I run into, but try interacting with Cody without using inline chat, then make changes to your text document and then start a new conversation, you should not see the error message about Cannot read properties of undefined (reading 'scheme'):