update build script to add the timestamps

lisp/build.el

@@ -327,11 +327,13 @@ Created with %c on <a href=\"https://www.archlinux.org/\">Arch</a> <a href=\"htt
 (defun z/build-full ()
   "Full rebuild: Org, assets, and search index."
   (interactive)
+  (message "🚧 Starting full rebuild at %s" (current-time-string))
   (setq z/build-full-rebuild t)
   (z/generate-all-files-org)
   (z/org-publish-quiet "org-roam" t)
   (z/org-publish-quiet "org-static" t)
-  (message "✅ Full rebuild complete"))
+  (message "✅ Full rebuild complete")
+  (message "🏁 Finished full rebuild at %s" (current-time-string)))
 
 (defun z/build-fast ()
   "Fast rebuild: Org + assets only (no JSON)."