The space-around alignment distributes space as 1-row gap / AB / 2-row
gap / CD / 1-row gap for a 6-row container with 2 content rows.
Expected value was "\nAB\n\nCD\n\n" but Ink produces "\nAB\n\n\nCD\n".
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Translates flex, direction, wrap, align, justify, gap, padding,
margin, width-height, position, display, and overflow tests from
Ink. Adds trimLines mode and trailing-newline strip to test helper.
Fixes Box type for alignContent (space-between/around/evenly) and
alignSelf (stretch/baseline).
21 tests fail due to behavioral differences (overflow clipping,
percentage dimensions, relative position offsets, align-content
space-* variants). These represent real gaps to investigate.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>