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

ts/namespaces/array.ts

@@ -31,7 +31,9 @@ export class ArrayMatchers<T> {
   toContainEqual(item: T) {
     return this.assertion.customAssertion(
       (value) => (value as T[]).some((e) => plugins.fastDeepEqual(e, item)),
-      `Expected array to contain equal to ${JSON.stringify(item)}`
+      (value) =>
+        `Expected array to contain equal to ${JSON.stringify(item)}` +
+        `\nReceived: ${JSON.stringify(value, null, 2)}`
     );
   }
 
@@ -55,6 +57,12 @@ export class ArrayMatchers<T> {
       `Expected array to be empty`
     );
   }
+  /**
+   * Alias for empty array check
+   */
+  toBeEmpty() {
+    return this.toBeEmptyArray();
+  }
 
   toHaveLengthGreaterThan(length: number) {
     return this.assertion.customAssertion(