docs: improve app environment descriptions

- Added descriptions to each environment
- Clarified usage of each environment

Author: fulleni

lib/app/config/app_environment.dart

@@ -1,6 +1,23 @@
+/// Defines the different application environments.
 enum AppEnvironment {
+  /// Represents the production environment.
+  ///
+  /// This environment is used for the live application, connecting to
+  /// production backend services and configurations.
   production,
-  developmentInMemory,
-  developmentApi, // New: For local Dart Frog API
+
+  /// Represents a demonstration environment with in-memory data.
+  ///
+  /// This environment is designed for showcasing the application's user
+  /// interface and features without requiring any external backend services.
+  /// All data operations are handled by mock data stored directly in memory,
+  /// eliminating the need for API access.
+  demo,
+
+  /// Represents a development environment connecting to a local API.
+  ///
+  /// This environment is used during local development, typically connecting
+  /// to a locally running Dart Frog backend API.
+  development,
   // Add other environments like staging, etc. as needed
 }