Improve performance for scenes with many entities & transforms

[Wumpf]

What

Not super significant unfortunately, in one badly affected scene I went from ~130ms to ~110ms. It's probably better in those that aren't using any transforms at all.
We need to do some more general overhaul there and imho at that point we might as well start thinking more seriously about range queries for transforms. See among others:

• Simplify transform hierarchy walk & computation #7025
• "Visible Time Range" doesn't work with transforms #723

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