Layout

src/export/layout/units.ts — UM_PER_INCH=25400, ptToUm, umToPt, pxToUm, twipToUm, emuToUm, mmToUm, clampUm.

src/export/layout/text.ts — FontMetrics, getFontMetrics, breakLines (greedy, \n/\t, fallback), estimateRunWidth, findMissingGlyphs.

src/export/layout/pagination.ts — paginateDocument(doc, {widows,orphans}) → {pages, diagnostics, hash}. Flow helpers: layout-types.ts, layout-flow.ts, layout-blocks.ts, layout-structured.ts (table / columns / image / equation-block / page-break).

See src/export/layout/index.ts (buildLayout).