Improved automatic view creation heuristic, major speedup for scenes with many entities

[Wumpf]

What

What space views get spawned is no longer determined by a centralized heuristic, but instead by one distributed to each space view class. Each of those heuristics can make much better use of existing information provided by store subscribers.

• Fixes most of Re-engineer the space-view heuristics engine #4388
  • a few things on the tracking issue still left to investigate
• Fixes When no heuristics match, still pick a fallback view if possible #3342
  • more "obsoleted" arguably: We originally had a hack that 1d tensor logging would display a bar chart. That's not actually desirable. There is still the open issue for the query now to not rely exclusively on indicators, but automatic view spawning is encouraged to do so. (Overall the workings and fault lines of these systems have shifted a lot since the ticket was filed.)
• Fixes Space view heuristics don't create 2D space view at paths where there's a 3D space view even if it is needed #4695
  • Looks like this now:
• Fixes Bad heuristics for objectron #4689
• Fixes Move heuristic for viable space view "candidates" to space view class #3079

Significant speedup for scenes with many entities (100+):

opf --no-frames
before: App::update 39.0ms, of which default_created_space_views 10.4ms
after: App::update 27.4ms, of which default_created_space_views 0.17ms

python/tests/many_entities (1000 individual points)
before: App:::update 151ms, of which default_created_space_views 124ms
after: App::update 22.6ms, of which default_created_space_views 0.06ms
(still pretty bad, but less so and for different reasons now!)

(numbers from my macbook on a release build. Actual numbers might differ by now, these are from last week. )

Checklist

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  • Using newly built examples: app.rerun.io
  • Using examples from latest main build: app.rerun.io
  • Using full set of examples from nightly build: app.rerun.io
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[github-actions]

Size changes

Name	main	4874/merge	Change
plots.rrd	194.56 kiB	204.80 kiB	+5.26%

[jleibs]

Nice work! I find this so much easier to reason about than the old implementation.

Most of my complaints aren't with this change, so much as the fact that it's now easier to see and discuss what I think are flawed heuristics in and of themselves. For merge-sanity I'm totally happy to defer any of those other changes to future-work now that we have this much cleaner framework for discussing the behavior in a per-space-view context.

[jleibs]

The need to instantiate this feels weird to me but I'm guessing the self in the signature stems from some context where we need to dynamically dispatch across a set of visualizers instead of being templated on <TVisualizer>?

[Wumpf]

yeah all these self-passings are about object safety really. We'd like this to be static but Rust makes this messy