feat: add single click mode (#1139)

frontend/src/i18n/en.json

@@ -174,6 +174,7 @@
     "globalRules": "This is a global set of allow and disallow rules. They apply to every user. You can define specific rules on each user's settings to override this ones.",
     "allowSignup": "Allow users to signup",
     "createUserDir": "Auto create user home dir while adding new user",
+    "singleClick": "Use single clicks to open files and directories",
     "insertRegex": "Insert regex expression",
     "insertPath": "Insert the path",
     "userUpdated": "User updated!",