Feature thinking toggle

[LifeJiggy]

✅ New Feature: Add "Enable Thinking" Checkbox to BrowserQwen UI

This PR introduces a new "Enable Thinking" checkbox to the BrowserQwen UI, providing users with direct control over the agent’s thinking mode.

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🚀 Motivation

Users requested the ability to disable the "Think" mode for Qwen3-VL-30B and other Qwen models in the BrowserQwen interface. This feature improves flexibility and user experience by allowing opt-in or opt-out of advanced thinking behaviors as needed.

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🛠️ Implementation Summary

• Added "Enable Thinking" checkbox to BrowserQwen UI.
• Available in Chat, Editor, and Pure Chat tabs.
• Allows users to enable or disable thinking mode for Qwen models (including Qwen3-VL-30B).
• Clean implementation with proper parameter passing and minimal UI disruption.

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📝 Reference

• Issue Qwen 3 VL 30B 无法关闭Think #720: User could not disable "Think" mode in BrowserQwen.

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💡 Feedback

Please share your thoughts on this feature, ideas for further improvements, or any concerns. The goal is to maximize user control and satisfaction with Qwen models.

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Thank you for reviewing! 🙌