internal: Bring back source compression in `base-db`

[davidbarsky]

As part of the new Salsa migration, I dropped source compression in source-db. We should consider bringing that back.

(Original context posted by @lnicola in #19429 (comment))

[ShoyuVanilla]

Just out of curiosity, could you explain me the reason it dropped? Maybe the previous compress text setting logic didn't work with new salsa, I guess?

[davidbarsky]

I was lazy and didn’t want to think about it when figuring out how to port base-db. I didn’t get around to reintroducing this once I did figure out base-db.

[ShoyuVanilla]

Thank you for the explanation. The salsa migration was quite a great work and I think that no one would say it was lazy 😄