Remove or replace the gear icon in Tools dropdown

Issue

The gear icon doesn't make sense in the chat dropdown. We should replace that with a "Tool" icon, or just remove it

See ToolSelector.tsx. The exact line in the code where the Gear icon is placed is right here.
Either remove the icon, or replace it with a "tool" icon using lucide-react.

change the icon. I have submitted a PR for this!

@divyanshsirohi

Thank you so much! @divyanshsirohi

Done!