boxel-motion improvements

[lukemelia]

• Add Split View example to boxel-motion test app as a study for the AI Assistant Panel animation
• Incorporate boxel-motion builds into CI
• Generalize fill behavior of behaviors rather than special casing StaticBehavior treatment
• Default StaticBehavior to a duration of 1, since you can now opt into forward fill
  • when using StaticBehavior with SpringBehavior, you don't know how long the animation will be, and you may want a static animation to persist for the duration of the animation
• Use context-relative bounds for removed sprites

extracted from #1097

[github-actions]

Test Results

550 tests  ±0   546 ✔️ ±0   8m 36s ⏱️ +39s
    1 suites ±0       4 💤 ±0 
    1 files   ±0       0 ❌ ±0 

Results for commit 609aaab. ± Comparison against base commit 24de03d.

♻️ This comment has been updated with latest results.

[lukemelia]

Screen.Recording.2024-03-20.at.4.35.09.PM.mov

[backspace]

@debugging is great 🤩

[lukemelia]

A few other thoughts, so I don't forget them:

1. Specifying to and from can be confusing. The more common case appears to be using captured to and/or from in combination with an "entrance" value for an Inserted Sprite and an "exit" value for a Removed Sprite
2. the strategy of cloning destroyed sprites to the orphans div under the animation context can cause problems for nested sprites. Given the structure AnimationContext > Sprite A > Sprite B... for animating Sprite B, Inserted and Kept animations are run with a parent of Sprite A, but Removed animations are run with a parent of the AnimationContext. Perhaps it should be cloned beneath Sprite A instead when Removed?

[ef4]

This seems fine as an incremental step. But in terms of the vision for how I think boxel-motion is supposed to work, fill doesn't really make sense.

The use case for boxel-motion is that you already have an initial and final DOM and the behaviors explain what happens in between those states. If behaviors are able to alter the final DOM, it seems like something about the architecture is getting muddied.