[MM-25648] api4: add user/bot convert endpoints (#14877)

* api4: add user/bot convert endpoints

* api4: add convert user/bot to local mode

* api4: fix linting issues

* api4/bot: reflect review comments

* api4: update convert user endpoint paths

* remove shadow decl

* fix translation problems

i18n/en.json

@@ -1,4 +1,8 @@
 [
+  {
+    "id": "",
+    "translation": ""
+  },
   {
     "id": "April",
     "translation": "April"