Uniform button variant in patient details page tabs and replace ButtonV2's with Button in entire codebase

[Mahendar0701]

We have different variants of buttons in each tab. A uniform variant would be more appropiate

[Mahendar0701]

@rithviknishad @Jacobjeevan i want to work on this. please assign this to me.

And also suggest which variant should be used accross all tabs? primary or black one?

[rithviknishad]

use the one in the "Schedule Appointment".

Also do ensure we have icons too for all those shown ☝

Also replace "ALL" usages of ButtonV2 in the codebase with shadcn's Button and delete ButtonV2

[rithviknishad]

@Mahendar0701 handle this too along with this:

#9718