[RTL] Add optional push_meta argument to control how meta underline is drawn.

[bruvzg]

• Adds option to hide underline or show it on hover for individual meta tags.

Supersede #89000

[Mickeon]

I'm questioning if META_UNDERLINE_NEVER is ever useful or if the behaviour with Images we talked about prior should be addressed, instead.

Like, I want to note you can already choose which meta tag has underlines and which does not, with push_underline. So the extra granularity feels a bit superfluous.

[Mickeon]

Review above still stands but I desire to have a long-living love relationship with this feature.

[akien-mga]

Thanks!