Platform guides, device groups, terminal tabs, pack README manuals and
logo credits move from Python tables to platforms/_guides.yml, checked
against the registry on load. A folder row without a path is the
registry's extract_to, written once.
Wiki pages place themselves in the navigation with order and nav_title
in their front matter. Generated docs/ and mkdocs.yml are unchanged.
The pack README's one-line install was written per platform: ROCKNIX and MiSTer had none, EmuDeck's Windows edition was told to open Konsole, and RomM users were sent to library/bios/ whatever their firmware template. The automatic section now follows each platform's install.detect systems, the EmuDeck and RomM manual steps name every layout, and the download page lists EmuDeck under Windows and macOS.