Start of pulling the menu system out of the 12k-line single-file
installer so individual menus can change without risking the rest of
the script (network, VNC, addons, etc). This is groundwork for the
planned web-based management UI, which will share the same lib/config.sh
read/write layer instead of duplicating it.
- lib/menu.sh: generic numbered-menu framework (auto-numbered entries,
"0" always exits/returns) plus the validated input helpers menus need.
- lib/config.sh: single load/save for config.json. Fixes a latent bug
where the old Sites menu wrote config.json without first loading
swipe/navigation/lockout settings, silently resetting them to
defaults on save.
- menus/sites.sh: Sites & Page Timing fully migrated - add/edit/delete/
reorder pages, set duration (auto-rotate/manual/hidden) and home page.
Also fixes an off-by-one in the ported reorder logic (moving an item
landed one slot short of the requested position) caught by testing.
- install.sh: new entry point for managing an already-installed kiosk
via `git clone` + `./install.sh`, wired to the Sites menu. Does not
yet replace first-time provisioning, which still uses the existing
single-file installer.
All new site CRUD/reorder/home-page paths were exercised against a
scratch config.json (add with/without basic auth, edit duration, set
home + timeout, 2- and 3-item reorders in both directions, delete) to
confirm the resulting config.json matches expectations.
