Converted main codebase to typescript

Signed-off-by: Taken <taken@mairimashita.org>

src/interfaces/Modal.ts

@@ -0,0 +1,8 @@
+import { ModalSubmitInteraction } from "discord.js"
+
+export default interface Modal {
+  name: string
+  description: string
+  type: "modal"
+  execute: (interaction: ModalSubmitInteraction) => Promise<void>
+}