feat: extended flex layout

[rauhryan]

What does this PR do?

Adds a slop spike to explore expanding flex sizing options

Closes #70
Closes #71

Type of change

• Bug fix
• Feature
• Refactor (no behavior change)
• Documentation
• Performance improvement
• Tests
• Chore (dependencies, CI, tooling)

Checklist

• All tests pass (pnpm test)
• Files are formatted (pnpm format)
• I have added/updated tests for my changes (if applicable)
• I have added a changeset

AI-generated code disclosure

• This PR includes AI-generated code

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npm i https://pkg.pr.new/@bomb.sh/tty@97

commit: 26ce90b

[github-actions]

Size Increased — +1.4 KB

130.9 KB unpacked

[rauhryan]

[codspeed]

Merging this PR will not alter performance

✅ 10 untouched benchmarks

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_{Comparing flex-sizing-70-71 (26ce90b) with main (628196c)¹}

Footnotes

1. No successful run was found on main (9e6f17b) during the generation of this report, so 628196c was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩

[rauhryan]

Note:

this revealed two issues

1. how should we deal with box-sizing and what happens when the layout engine positions an element on top of the border of a box

2. it revealed a small gotcha on how clays command order and our cell rendering logic works for text and border glyphs

[bombshell-cooper]

Changeset suggestion

This PR changes published packages but has no changeset.

View the proposed changeset

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Adds `layout.alignSelf` and `stretch()` for per-child cross-axis alignment in flex layouts.

`layout.alignSelf` accepts `auto`, `normal`, `stretch`, `center`, `start`, `end`, `flex-start`, and `flex-end`. `auto` (the default) inherits the parent's cross-axis alignment unchanged. `stretch` and `normal` expand auto-like cross sizes to fill the parent's content box; definite sizes (`fixed()`, `percent()`) remain definite. The new `stretch()` sizing helper explicitly fills the cross axis and can be used on either dimension independently of `alignSelf`.

Floating elements and root elements ignore `alignSelf`.

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