enable vi_mode in configs that don't have prompt_char

internal/wizard.zsh

@@ -1538,12 +1538,19 @@ function generate_config() {
       sub MULTILINE_FIRST_PROMPT_PREFIX ''
       sub MULTILINE_NEWLINE_PROMPT_PREFIX ''
       sub MULTILINE_LAST_PROMPT_PREFIX ''
-      uncomment prompt_char
       sub STATUS_OK false
       sub STATUS_ERROR false
     fi
   fi
 
+  if [[ $style == (classic|rainbow) ]]; then
+    if (( num_lines == 2 && ! left_frame )); then
+      uncomment prompt_char
+    else
+      uncomment vi_mode
+    fi
+  fi
+
   (( empty_line )) && sub PROMPT_ADD_NEWLINE true || sub PROMPT_ADD_NEWLINE false
 
   sub INSTANT_PROMPT $instant_prompt