[MM-52574] Add back PermissionUseSlashCommands (#23476)

server/public/model/permission.go

@@ -21,6 +21,10 @@ type Permission struct {
 
 var PermissionInviteUser *Permission
 var PermissionAddUserToTeam *Permission
+
+// Deprecated: PermissionUseSlashCommands is not longer used. It's only kept for backwards compatibility.
+// See https://mattermost.atlassian.net/browse/MM-52574 for more details.
+var PermissionUseSlashCommands *Permission
 var PermissionManageSlashCommands *Permission
 var PermissionManageOthersSlashCommands *Permission
 var PermissionCreatePublicChannel *Permission
@@ -389,6 +393,12 @@ func initializePermissions() {
 		"authentication.permissions.add_user_to_team.description",
 		PermissionScopeTeam,
 	}
+	PermissionUseSlashCommands = &Permission{
+		"use_slash_commands",
+		"authentication.permissions.team_use_slash_commands.name",
+		"authentication.permissions.team_use_slash_commands.description",
+		PermissionScopeChannel,
+	}
 	PermissionManageSlashCommands = &Permission{
 		"manage_slash_commands",
 		"authentication.permissions.manage_slash_commands.name",
@@ -2308,6 +2318,7 @@ func initializePermissions() {
 	}
 
 	ChannelScopedPermissions := []*Permission{
+		PermissionUseSlashCommands,
 		PermissionManagePublicChannelMembers,
 		PermissionManagePrivateChannelMembers,
 		PermissionManageChannelRoles,