Allow searching within a single conversation

As far as I can see, currently it isn’t possible to search within a single conversation on the macOS app. This actually makes the app less useful than the web version of ChatGPT since it makes it harder to find specific messages in a conversation. Every time I launch a search, it only search for conversations in in the conversation list (thankfully by including the message content), but this is less useful when conversations are long and wordy.