Module caption 

Caption block — wrapped text on top of a rounded rect background (M-TEXT.9 / AUT-83).

Composition only; no new shaders. Layout works in NDC throughout:

1. Construct a CaptionBlock with text, style, max_width_ndc, and padding_ndc.
2. Call CaptionBlock::layout with the crate::text::TextTexturePipeline to measure the text and produce a list of scene nodes:
   • a background Graphics rounded rect sized to the wrapped text + padding;
   • a Sprite carrying the rendered text texture, positioned inside the padding rect.
3. Caller attaches both nodes to a Container (or directly to the stage); the container’s transform handles position.

Honors WispTextStyle::align (the text texture itself respects the style’s alignment) and line_height (cosmic-text handles wrap + line metrics).

Structs

CaptionBlock

Builder for a wrapped caption block with a rounded-rect background.

CaptionLayout

Result of laying out a CaptionBlock.