Chat Actions Button State and Refresh Disruption to Stream.

[Ericzhou-ez]

1. Chat button state is not synced properly with the stream. When the message begins streaming in the status of the button becomes "nothing to send" or "send" depending on the content in the text-input, when it should enable the user to terminate the stream.
2. When sending a message and a manual refresh occurs before the first token arrives eventhough the current model selected (eg. GPT5) responds to the first message the model selector and subsequent messages are responded by Gemini 2.5 flash lite.