message: allow SlashClient in slash decorators
diff: @@ -266,6 +266,7 @@ export class Client extends EventEmitter {
  this.gateway = new Gateway(this, token, intents)
  }
  + /** Wait for an Event (optionally satisfying an event) to occur */
  async waitFor<K extends keyof ClientEvents>(
  event: K,
  checkFunction: (...args: ClientEvents[K]) => boolean,
  @@ -308,7 +309,7 @@ export function event(name?: keyof ClientEvents) {
  /** Decorator to create a Slash Command handler */
  export function slash(name?: string, guild?: string) {
  - return function (client: Client | SlashModule, prop: string) {
  + return function (client: Client | SlashClient | SlashModule, prop: string) {
  if (client._decoratedSlash === undefined) client._decoratedSlash = []
  const item = (client as { [name: string]: any })[prop]
  if (typeof item !== 'function') {
  @@ -324,7 +325,7 @@ export function slash(name?: string, guild?: string) {
  /** Decorator to create a Sub-Slash Command handler */
  export function subslash(parent: string, name?: string, guild?: string) {
  - return function (client: Client | SlashModule, prop: string) {
  + return function (client: Client | SlashModule | SlashClient, prop: string) {
  if (client._decoratedSlash === undefined) client._decoratedSlash = []
  const item = (client as { [name: string]: any })[prop]
  if (typeof item !== 'function') {
  @@ -364,7 +365,7 @@ export function groupslash(
  /** Decorator to add a Slash Module to Client */
  export function slashModule() {
  - return function (client: Client, prop: string) {
  + return function (client: Client | SlashClient, prop: string) {
  if (client._decoratedSlashModules === undefined)
  client._decoratedSlashModules = []
  