prevent a user with no chat privileges from inviting any player to a guild or party (#10194)

This is because they could use private group chat messages to bypass
the restriction on talking to other players.

website/common/locales/en/groups.json

@@ -256,6 +256,7 @@
   "userCountRequestsApproval": "<%= userCount %> request approval",
   "youAreRequestingApproval": "You are requesting approval",
   "chatPrivilegesRevoked": "Your chat privileges have been revoked.",
+  "cannotInviteWhenMuted": "You cannot invite anyone to a guild or party because your chat privileges have been revoked.",
   "newChatMessagePlainNotification": "New message in <%= groupName %> by <%= authorName %>. Click here to open the chat page!",
   "newChatMessageTitle": "New message in <%= groupName %>",
   "exportInbox": "Export Messages",

website/server/controllers/api-v3/groups.js

@@ -1138,6 +1138,7 @@ async function _inviteByEmail (invite, group, inviter, req, res) {
  *
  * @apiError (401) {NotAuthorized} UserAlreadyInvited The user has already been invited to the group.
  * @apiError (401) {NotAuthorized} UserAlreadyInGroup The user is already a member of the group.
+ * @apiError (401) {NotAuthorized} CannotInviteWhenMuted You cannot invite anyone to a guild or party because your chat privileges have been revoked.
  *
  * @apiUse GroupNotFound
  * @apiUse UserNotFound
@@ -1150,6 +1151,8 @@ api.inviteToGroup = {
   async handler (req, res) {
     let user = res.locals.user;
 
+    if (user.flags.chatRevoked) throw new NotAuthorized(res.t('cannotInviteWhenMuted'));
+
     req.checkParams('groupId', res.t('groupIdRequired')).notEmpty();
 
     if (user.invitesSent >= MAX_EMAIL_INVITES_BY_USER) throw new NotAuthorized(res.t('inviteLimitReached', { techAssistanceEmail: TECH_ASSISTANCE_EMAIL }));