Replace the outdated Calibre-wireless/Basic-Auth instructions with the
actual current flow: install the bookhoard.koplugin plugin, enter the
server URL in the plugin menu, then approve the pending registration
from Settings → Devices. Registration tokens are delivered to the
plugin automatically after approval (5-minute expiry), so no
credentials are ever typed on the device.
Also document bidirectional sync of position, bookmarks, highlights
(colors mapped between web and KOReader palettes), and notes, plus
format-aware SHA-256 book matching, OPDS delivery, and trimmed
troubleshooting sections covering the new registration flow.