feat(zshrc): add cleanzip helper for macOS junk in archives

Small portable utility next to cheat/speedtest; strips __MACOSX
and .DS_Store entries via zip -d.

.zshrc

@@ -196,6 +196,11 @@ dadjoke() {
     curl https://icanhazdadjoke.com
 }
 
+# Strip macOS junk from a zip (requires `zip`). Usage: cleanzip archive.zip
+cleanzip() {
+    zip -d "$@" __MACOSX/\* \*/.DS_Store
+}
+
 # Find geo info from IP
 ipgeo() {
     # Specify ip or your ip will be used