Ensure that text is vertically centered

@srujner has noticed in a couple of cases that text that should be vertically centered isn't. Instead, the text is higher than it should be.

- https://github.com/getodk/central/issues/671#issuecomment-2252323837
- The count in the badge is aligned with the rest of the text in the navigation tab, which is great. But the text is also supposed to be vertically centered within the badge, and that's not happening currently. I thought initially that the badge was misaligned relative to the text, but now I'm thinking that the issue is with the text itself.
- https://github.com/getodk/central/issues/728#issuecomment-2792321249
- Specifically: "4.2 The text "New Entity Lists..." is not exactly in the center"
- I'm noticing in screenshots like [this one](https://github.com/getodk/central/issues/728#issuecomment-2792116638) from @srujner that the button text isn't vertically centered within the button.

I haven't been able to reproduce this on my machine. I wonder if it could be an issue with fonts: I've noticed that the font that's shown for @srujner is different from the font I see.

Start by reviewing the screenshots and the linked discussions in issues 671 and 728, then compare the font and vertical alignment in the affected badges, navigation text, and buttons. Reproduce the reported differences across environments before identifying the relevant UI entry points; done means the cited text is vertically centered without breaking the surrounding layout.

Written by the indexing model from the issue text.