I'm still confused about that last bubble. The previous translation was more literally correct but doesn't make any more sense. What exactly is Sakuya meaning here?
As romanized, it goes "Tekitou ni (g/)kiri ageru deshou"

Maybe Sakuya has somehow enlarged the floor below and forgot to restore it to it’s original size, which would make cleaning a lot easier. Instead she expects Sanae to give up afer a while because it’s such a huge area.

Wait... I thought her power was just time manipulation. Can she alter space too?

There's a whole lot of theory of relativity stuff but essentially, Sakuya can control time.Ttherefore, she can control "space" as well. After defeating Patchouli, she says something like "There's someone here who likes playing with dimensions/space."

The Wiki also notes that Sakuya is the one responsible for the mansion, especially the library, being so much larger on the inside than outside.