docs(wiki): rewrite First Dive to match real onboarding and edit form

ericgriffin committed Jun 16, 2026

docs: migrate full user guide to the wiki as the single source of truth Add the 9 remaining guide pages (Installation, First Dive, Dive Logging, Dive Sites, Equipment, Statistics, Import/Export, Dive Computers, Settings), rewrite Home as the getting-started landing page, and expand the sidebar. Screenshot placeholders stripped, guide/*.md links converted to wiki links, and broken features/* links removed. The guide is being removed from the app repo so the wiki is the sole copy to maintain.

ericgriffin committed Jun 15, 2026