Add Writing Desk storage and menu foundation

README.md

@@ -20,6 +20,11 @@ Each vial holds 16 ink units, and the default link-panel cost is two units.
 The spent vial returns a glass bottle. Server owners can adjust the symbol-copy
 and link-panel costs in the `writing` section of `rivencraft-server.toml`.
 Symbol-page transcription will become available through the Writing Desk.
+The Writing Desk is now craftable from planks, a glass bottle, and a feather.
+Its four collection tabs, ink/source/page work slots, and inventory persist
+through world saves; breaking it drops stored contents. The desk screen is a
+functional foundation styled after Legacy's left tabs, central writing surface,
+and right inventory. Transcription controls are not implemented yet.
 
 ## Linking Book