fix: replace help dialog with modal

[im-adithya]

DialogTrigger didn't work properly because it uses onPress which works differently in android (if you tap it and move away from the button/touchable opacity it won't trigger the function, as opposed to the onPressIn that we are replacing it with now which triggers as soon as the icon is tapped on)

I also tried to increase the padding to make the button bigger so we don't have to replace the Dialog but the Navigation bar already leaves space on the right. And we already are using onPressIn for the X icon when there are wallets available which works fine so I proceeded with this.

Screenshot

[reneaaron]

Did you check whether updating the rn-primitives / nativewind components / libs could possibly fix this problem?

By not using these components we lose e.g. darkmode ability and would need to define colors / paddings / etc. all on our own 🤔

[im-adithya]

DialogTrigger component is directly imported from rn-primitives so we can't change that code to onPressIn instead of onPress, and the Modal component makes the whole thing easy align with nativewind so I think this is good (updated dark mode screenshot in the PR main comment)