Remove the scary-looking notification when a chat reaches its context limit

[taylorsperry]

Today, users see a very scary-looking notification when a chat reaches its context limit. We added this just before the Dec release and we know that it's created a lot of confusion for users. We're taking other steps #2600 to discourage users from long, ongoing chats which we expect to help mitigate Cody's forgetfulness.

Once we have a better understanding of the impact on users when Cody's context window is full, we can make a decision about what else we need to do to address it.

Opened in favor of #2857.

[kalanchan]

fixed in #2891