refactor: add generic Type and Defined<Type>

Author: sciborrudnicki

packages/type/src/guard/lib/guard-defined.func.ts

@@ -11,4 +11,4 @@ import { ResultCallback } from '../../type/result-callback.type';
  * @returns A `boolean` indicating whether or not the `value` is defined, if `undefined` then returns `never`.
  */
 export const guardDefined: GuardDefined = <Type>(value: Type, callback?: ResultCallback): value is Defined<Type> =>
-  isDefined(value, callback);
+  isDefined<Type>(value, callback);

packages/type/src/is/type/is-defined.type.ts

@@ -1,2 +1,3 @@
+import { Defined } from '../../type/defined.type';
 import { ResultCallback } from '../../type/result-callback.type';
-export type IsDefined = (value: unknown, callback?: ResultCallback) => boolean;
+export type IsDefined = <Type>(value: unknown, callback?: ResultCallback) => value is Defined<Type>;