Solara viz: use_task for non-threaded continuous play

[Corvince]

This is an alternative to #2303

While investigating #2303 I realized that use_thread is deprecated and recommended to replace with use_task, which also allows not using a thread at all, but a coroutine. This allows this version to also work in environments where threading can be problematic (colab) or isn't available at all (Pyodide, WASM, etc.). It also avoids possible issues with threads running in the background forever.

It also runs blazingly fast!

screen-capture.1.webm

[github-actions]

Performance benchmarks:

Model	Size	Init time [95% CI]	Run time [95% CI]
BoltzmannWealth	small	🔴 +6.8% [+5.0%, +8.6%]	🔴 +8.0% [+6.8%, +9.2%]
BoltzmannWealth	large	🔵 -1.4% [-2.9%, -0.5%]	🔵 -0.4% [-0.8%, +0.0%]
Schelling	small	🔵 -0.2% [-0.4%, +0.0%]	🔵 -0.2% [-0.4%, -0.1%]
Schelling	large	🔵 -0.4% [-0.5%, -0.1%]	🔵 -0.0% [-0.3%, +0.2%]
WolfSheep	small	🔵 -0.4% [-0.7%, -0.2%]	🔵 -0.2% [-0.4%, -0.1%]
WolfSheep	large	🔵 -0.4% [-0.8%, +0.0%]	🔵 -0.4% [-0.9%, +0.0%]
BoidFlockers	small	🔵 -0.5% [-0.9%, -0.2%]	🔵 +0.5% [-0.2%, +1.2%]
BoidFlockers	large	🔵 -0.2% [-0.6%, +0.1%]	🔵 -0.4% [-1.3%, +0.5%]

[rht]

Shouldn't 1 be play_interval?

[Corvince]

oops, of course. Thats why we have code reviews I guess :)

[EwoutH]

Awesome stuff!

As a reference, use_task is currently in the Solara Lab, which contains parts of Solara that are slightly experimental. They are currently considering stabilizing it, but if any changes in the meantime, this is probably the issue to track:

• Deprecate use_thread, and take use_task and @task out of lab widgetti/solara#784