pptx-author

STEP 2 of the PPTX-from-layouts pipeline. Write a slide deck in markdown using the [HINT: layout_name] system so each slide targets a real template layout, then lint it before rendering. Use when the user wants to "draft slides", "write a deck outline", "author presentation markdown", "add layout hints", or has a layout catalog from Step 1 and needs to turn content into slides. Pairs with pptx-profile (Step 1) and…