Add wheel item type and random step/wall movement audio

client/public/version.js

@@ -1,3 +1,3 @@
 // Maintainer-controlled web client version.
 // Format: YYYY.MM.DD Rn (example: 2026.02.20 R2)
-window.CHGRID_WEB_VERSION = "2026.02.20 R69";
+window.CHGRID_WEB_VERSION = "2026.02.21 R70";