Infer partition size for FixedSizeList-backed components

[oxkitsune]

Related

Closes #9171

What

This lets the user do:

rr.send_columns(
  "random_3d_points",
  indexes=[times],
  columns=rr.Points3D.columns(positions=np.random.random((len(times), 21, 3))),
)

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[Wumpf]

pixi.lock change is suspicious, why did it change here?
Cool that this just works :O. But needs a test or snippet using this
Could docs/snippets/all/archetypes/points3d_column_updates.py be updated for that?

[Wumpf]

Could docs/snippets/all/archetypes/points3d_column_updates.py be updated for that?

ah the answer is certainly no since inhomogenous partitions sizes can't be detected

[oxkitsune]

pixi.lock change is suspicious, why did it change here?

I think this happened because @jleibs updated on a machine with cuda available, and I synced it on my mac?

[Wumpf]

Or maybe you're running an old pixi. We just updated #9203

[oxkitsune]

Or maybe you're running an old pixi. We just updated #9203

❯ pixi --version
pixi 0.41.4

I think I'm up to date right?

[Wumpf]

love the new test, should have had this from the very start when this utility was first introduced

[Wumpf]

phew, lotsa snippet work. looking great