fix(ui): Clean up the UI for the 6POS switch on the radio/simulator

[philmoz]

Change 6POS switch UI:

• Box for selected position fits between the tick lines
• Center the position number in the box

Before:

After:

[Eldenroot]

Thank you! I like your work and recent PRs! Keep good work!

[gagarinlg]

I like it

[philmoz]

I've added the fix for issue #2818 that was suggested in that issue thread.

[gagarinlg]

Did anyone test this with the NV14 simu/simulator?

[mha1]

Did anyone test this with the NV14 simu/simulator?

I'll set it up

[mha1]

Did anyone test this with the NV14 simu/simulator?

Well, it seems NV14 doesn't have a 6Pos. And shouldn't have flight mode texts longer than 6 characters. This is not releated to this PR. Want me to put in an issue?

[philmoz]

Closing in favour of #2893 which is a better solution.

[mha1]

I take no credit for #2893. Couldn't have done it without input from @eshifri, @gagarinlg and @philmoz. Thank you for the joint effort to solve this what seemed at first very simple problem.