Polish: VaBadge

[asvae]

We did badge improvements (#3246), but there are a couple of things not covered by issue and PRs:

Component

• We need a floating prop (see Quasar). Right now - when you use slot - it's floating, and when you don't - it's not. That looks arbitrary to me.
• Demos are not in great shape (see Stories rework: VaBadge #3647).

Docs

• offset prop is extremely poorly documented, we need to document all usage cases (single number, array, strings, rems/percents etc)
• It's not possible to set different border color as it's getting overriden by :styles. We either want to dispose of borders or most probably make them operational.
• Default example makes no sense for docs (it makes sense for demos though). I suggest removing it for now, and later on - we can have either rich example or playground instead.
• Right now in examples to make badge work with icon and avatar components - we use offset. That's not great - these components should work properly with each other out of the box. It could be achieved by either some styling tweak when particular component is detected or by changing default behaviour of badge.
• placement prop description (in table) should have full information about the prop usage. Example could have only high level description.
• preset prop description should have link to preset usage page (also apply to other pages - prop should reuse the same values)