Add .isEmpty term entry for Dart Map

Adds documentation for the Dart Map `.isEmpty` property, including a brief
introduction, syntax, and a usage example aligned with Docs guidelines.

Author: omkarhole

content/dart/concepts/map/terms/is-empty/is-empty.md

@@ -0,0 +1,69 @@
+---
+Title: '.isEmpty'
+Description: 'Checks if a Map contains no key-value pairs.'
+Subjects:
+  - 'Computer Science'
+  - 'Code Foundations'
+Tags:
+  - 'Dart'
+  - 'Map'
+  - 'Properties'
+CatalogContent:
+  - 'learn-dart'
+  - 'paths/computer-science'
+---
+
+In Dart, the **`.isEmpty`** property is used to check if a `Map` contains no key-value pairs. If the map is empty, the property returns `true`. Otherwise, it returns `false`.
+
+## Syntax
+
+```pseudo
+mapName.isEmpty
+```
+
+- `mapName`: The `Map` to be checked.
+
+## Example
+
+The following example demonstrates the usage of the `.isEmpty` property:
+
+```dart
+void main() {
+  // Creating an empty Map
+  Map<String, int> emptyCart = {};
+
+  // Creating a Map with items
+  Map<String, int> fruitCart = {'Apple': 3, 'Banana': 5};
+
+  // Checking if the maps are empty
+  print(emptyCart.isEmpty);
+  print(fruitCart.isEmpty);
+}
+```
+
+The above code produces the following output:
+
+```shell
+true
+false
+```
+
+The `.isEmpty` property can also be used in conditional statements:
+
+```dart
+void main() {
+  Map<String, String> userInfo = {};
+
+  if (userInfo.isEmpty) {
+    print('No user data available.');
+  } else {
+    print('User data found.');
+  }
+}
+```
+
+The above code produces the following output:
+
+```shell
+No user data available.
+```