Add Quick Start tutorial and Command Reference to NEOS-BREAKTHROUGH.html

Replace the 4 section-local terminal demos with two comprehensive new
sections: an 8-step Quick Start walkthrough (section 08) and a full
Command Reference with 9 expandable categories covering all ~42 commands
(section 17). Renumber sections 08-19 to 09-21 to accommodate.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: Samuele95