Do not number org headings

Never type a number into an org heading. Write the bare title and let org number the section.

Why: Marco flagged it on the market data design document, where every second-level heading carried a manual number. Each one rendered as 4.1. 1. What is already settled, with org's number and the manual number side by side. The design document's 16 third-level headings carried a second, independent numbering scheme, and the prose cross-referenced sections by the manual numbers rather than the ones on screen.

How to apply: When writing or editing any org document, write headings as bare titles. When prose cross-references a section, use the number org will produce, counted from the top of the document.