MM-33903 rename slash commands & permission (#17494)

- rename slash commands
    - "remote" -> "secure-connection"
    - "share" -> "share-channel"
- change status icons to text (translated)
- remove channel invite "Description" field
- rename permission "manage_remote_clusters" -> "manage_secure_connections"

app/app_test.go

@@ -182,7 +182,7 @@ func TestDoAdvancedPermissionsMigration(t *testing.T) {
 		"system_admin": allPermissionIDs,
 	}
 	assert.Contains(t, allPermissionIDs, model.PERMISSION_MANAGE_SHARED_CHANNELS.Id, "manage_shared_channels permission not found")
-	assert.Contains(t, allPermissionIDs, model.PERMISSION_MANAGE_REMOTE_CLUSTERS.Id, "manage_remote_clusters permission not found")
+	assert.Contains(t, allPermissionIDs, model.PERMISSION_MANAGE_SECURE_CONNECTIONS.Id, "manage_secure_connections permission not found")
 
 	// Check the migration matches what's expected.
 	for name, permissions := range expected1 {