chore(ui) - network timeout error handling

[andrewrisse]

When sending a message to the API and it times out, the UI gives no feedback about a pending response.

You can test this by running the app locally and disabling tailscale. If you send a message, the network tab shows the request pending, but no indication is seen on the UI and it appears to just be hanging. We should set a timeout and handle it with a toast network error message.