feat: add tests for isValidPageSize and isValidPageNumber methods

src/models/ArgumentValidator.ts

@@ -31,7 +31,7 @@ export class ArgumentValidator {
    * @returns {boolean} - True if the value is a valid page size; otherwise, false.
    * @remarks - A valid page size is a number greater than 0 and less than or equal to 1000.
    */
-  public static isValidPageSize(value: number): boolean {
+  public static isValidPageSize(value: number | null | undefined): boolean {
     return value > 0 && value <= 1000;
   }
 
@@ -40,7 +40,7 @@ export class ArgumentValidator {
    * @returns {boolean} - True if the value is a valid page number; otherwise, false.
    * @remarks - A valid page number is a number greater than 0.
    */
-  public static isValidPageNumber(value: number): boolean {
+  public static isValidPageNumber(value: number | null | undefined): boolean {
     return value > 0;
   }
 }