feat(core): Add new matchers and improve negation messaging

test/test.negation.ts

@@ -0,0 +1,22 @@
+import { tap, expect as tExpect } from '@push.rocks/tapbundle';
+import * as smartexpect from '../dist_ts/index.js';
+
+tap.test('negation message for numeric matcher', async () => {
+  try {
+    smartexpect.expect(5).not.toBeGreaterThan(3);
+    throw new Error('Assertion did not throw');
+  } catch (err: any) {
+    tExpect(err.message).toEqual('Expected number not to be greater than 3');
+  }
+});
+
+tap.test('negation message for string matcher', async () => {
+  try {
+    smartexpect.expect('hello').not.string.toInclude('he');
+    throw new Error('Assertion did not throw');
+  } catch (err: any) {
+    tExpect(err.message).toEqual('Expected string not to include "he"');
+  }
+});
+
+export default tap.start();