Made interfaces for delegates

Because built-in `Function` is not flexible

src/utils/functions/async-func.ts

@@ -0,0 +1,16 @@
+/**
+ * Represents an async function that takes any number of arguments of type `P` and returns a value of type `R`.
+ *
+ * @template P - An array of parameter types.
+ * @template R - The return type of the function.
+ */
+export interface AsyncFunc<P extends unknown[] = unknown[], R = unknown> {
+    /**
+     * Calls the function with the specified arguments.
+     *
+     * @param args The arguments to pass to the function.
+     *
+     * @returns A promise resolving to the result of calling the function.
+     */
+    (...args: P): Promise<R>;
+}

src/utils/functions/func.ts

@@ -0,0 +1,16 @@
+/**
+ * Represents a function that takes any number of arguments of type `P` and returns a value of type `R`.
+ *
+ * @template P - An array of parameter types.
+ * @template R - The return type of the function.
+ */
+export interface Func<P extends unknown[] = unknown[], R = unknown> {
+    /**
+     * Calls the function with the specified arguments.
+     *
+     * @param args The arguments to pass to the function.
+     *
+     * @returns The result of calling the function.
+     */
+    (...args: P): R;
+}