feat: Enable new prompt input while waiting for an answer

[bytrangle]

Describe Your Changes

• Remove disabling of the textarea in ChatInput component. This allows users to type new question while waiting for the answer for the previous question.
• Modify the conditions for sending prompt so that a prompt won't be sent if the agent is generating an answer for the previous prompt.

Fixes Issues

• Closes idea: allow text entry during answer generation #6343

Self Checklist

• Added relevant comments, esp in complex areas
• Updated docs (for bug fixes / features)
• Created issues for follow-up changes or refactoring needed

[Copilot]

Pull Request Overview

This PR enables users to type new prompts while waiting for responses from the chat agent by removing the textarea disable behavior and updating send conditions.

• Removed textarea disabling when streaming content is active
• Modified prompt sending logic to prevent sending while agent is generating responses
• Updated conditional formatting for better code readability

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[Copilot]

Pull Request Overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 1 comment.

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[Copilot]

Pull Request Overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.

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[bytrangle]

Hello @LazyYuuki. I'd appreciate your feedback when you get a chance.