Add Legacy-style Book Binder

README.md

@@ -59,6 +59,22 @@ copy selection is checked by the server.
 Selecting a stored page on the desk surface shows its Legacy-proportioned
 portrait preview and name above the player inventory.
 
+## Book Binder
+
+Craft a Book Binder from three iron ingots and five planks. Put leather or an
+empty Notebook in the left cover slot. Enter a title, then place a Link Panel
+Page first in the horizontal page strip. Click a page in the strip with a
+written Page on the cursor to insert it before that position; click it with an
+empty cursor to take it out. The arrows or mouse wheel scroll through up to
+27 written Pages. Clicking the strip with a filled Notebook imports its Pages
+at that position and leaves the emptied Notebook on the cursor. The right slot
+outputs a Descriptive Book once the title, cover, and Link Panel are present.
+Inputs are consumed only when the result is taken.
+
+The completed book receives its Age identity when assembled. With only a Link
+Panel, it describes a randomly generated Age. Its writing is stored on the
+book; Milestone 5 will interpret additional symbols during Age generation.
+
 ## Linking Book
 
 Craft a Linking Book from a vanilla book and an ender pearl, then use it in the