feat: add errout for interactive for script support and atty for clean output

crates/gitnow/include/shell/zsh.sh

@@ -0,0 +1,15 @@
+function git-now {
+  choice=$(gitnow "$@")
+    if [[ $? -ne 0 ]]; then
+    return $?
+  fi
+  
+  cd "$(echo "$choice" | tail --lines 1)"
+}
+
+function gn {
+  git-now "$@"
+  if [[ $? -ne 0 ]]; then
+    return $?
+  fi
+}