Add unit tests for Assert class methods

- Introduced tests for `greaterThanEq`, `lessThanEq`, and `integerish` methods.
- Validated exception throwing with default and custom messages.
- Ensured correct behavior for valid inputs across scenarios.

Author: georgedeploy

tests/Unit/Code/Assert/AssertTest.php

@@ -0,0 +1,55 @@
+<?php
+
+declare(strict_types=1);
+
+use PhpTypedValues\Code\Assert\Assert;
+use PhpTypedValues\Code\Exception\TypeException;
+
+it('greaterThanEq throws with default message when empty', function (): void {
+    expect(fn() => Assert::greaterThanEq(0, 1, ''))
+        ->toThrow(TypeException::class, 'Expected a value greater than or equal to the minimum');
+});
+
+it('greaterThanEq throws with custom message when provided', function (): void {
+    expect(fn() => Assert::greaterThanEq(0, 1, 'custom gt= message'))
+        ->toThrow(TypeException::class, 'custom gt= message');
+});
+
+it('greaterThanEq does not throw when valid', function (): void {
+    Assert::greaterThanEq(1, 1, '');
+    Assert::greaterThanEq(2, 1, 'anything');
+    expect(true)->toBeTrue();
+});
+
+it('lessThanEq throws with default message when empty', function (): void {
+    expect(fn() => Assert::lessThanEq(2, 1, ''))
+        ->toThrow(TypeException::class, 'Expected a value less than or equal to the maximum');
+});
+
+it('lessThanEq throws with custom message when provided', function (): void {
+    expect(fn() => Assert::lessThanEq(3, 1, 'custom lt= message'))
+        ->toThrow(TypeException::class, 'custom lt= message');
+});
+
+it('lessThanEq does not throw when valid', function (): void {
+    Assert::lessThanEq(1, 1, '');
+    Assert::lessThanEq(1, 2, 'anything');
+    expect(true)->toBeTrue();
+});
+
+it('integerish throws with default message when empty', function (): void {
+    expect(fn() => Assert::integerish('5.5', ''))
+        ->toThrow(TypeException::class, 'Expected an "integerish" value');
+});
+
+it('integerish throws with custom message when provided', function (): void {
+    expect(fn() => Assert::integerish('foo', 'custom integerish message'))
+        ->toThrow(TypeException::class, 'custom integerish message');
+});
+
+it('integerish does not throw for integerish values', function (): void {
+    Assert::integerish('5', '');
+    Assert::integerish('5.0', '');
+    Assert::integerish(5, '');
+    expect(true)->toBeTrue();
+});