Adds Shared Channel related API endpoints (#27436)

* Adds Shared Channel management API endpoints

New endpoints for the following routes are added:

- Get Shared Channel Remotes by Remote Cluster at `GET
/api/v4/remotecluster/{remote_id}/sharedchannelremotes`
- Invite Remote Cluster to Channel at `POST
/api/v4/remotecluster/{remote_id}/channels/invite`
- Uninvite Remote Cluster to Channel at `POST
/api/v4/remotecluster/{remote_id}/channels/uninvite`

These endpoints are planned to be used from the system console, and
gated through the `manage_secure_connections` permission.

* Adds i18n messages for API errors

* Fix pagination flaky test

* Fix linter

* Adds the posibility of filtering shared channel remotes by home

---------

Co-authored-by: Mattermost Build <build@mattermost.com>

server/public/model/shared_channel.go

@@ -263,6 +263,8 @@ type SharedChannelRemoteFilterOpts struct {
 	ChannelId       string
 	RemoteId        string
 	InclUnconfirmed bool
+	ExcludeHome     bool
+	ExcludeRemote   bool
 }
 
 // SyncMsg represents a change in content (post add/edit/delete, reaction add/remove, users).