Description
Render the current buffer's text smartly laid out into a 4:5 (1080x1350) tall JPG for social posting. Sibling to the HTML export (-e). Open Qs: auto font-size/scale to fit, multi-image overflow when text too long, theme colors reuse from preview/export, CLI flag (e.g. -j/--jpg). Smart layout: margins, line wrap, vertical centering/balance.
Acceptance Criteria
- #1 A buffer exports to a 1080x1350 (4:5) JPG via a CLI flag
- #2 Text is laid out legibly with sensible margins and wrapping
- #3 Theme colors match preview/export house style