collectBookData() was only extracting steps for 3 hardcoded sections
(membership, sports-activity, treasury) using regex on view files.
All other sections (45 of 48) were passed without steps, rendering
only subtitle text in the PDF. Now calls TutorialRegistry::getSteps()
for every tutorial in every section.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>