Implement SettingsView for User Configurable Settings

This commit introduces the `SettingsView` class, which is responsible for rendering the user interface for the settings feature of the app. This View is associated with the `SettingsViewModel` for state management and logic.

Features Represented in this View:
- Dark Mode: A switch to enable or disable Dark Mode.
- Developer Mode: A switch to enable or disable Developer Mode.
- Base URL: A text field to input and configure the Base URL.
- Continuous Mode Steps: User-friendly '+' and '-' buttons allowing users to configure the number of steps for continuous mode.

The `SettingsView` utilizes the Flutter `ListView` to display various settings options, providing an intuitive and user-friendly experience. It employs reactive state management using the `Provider` package, ensuring that any state changes in the associated ViewModel are reflected immediately in the View. Proper documentation and comments have been added for better code readability and maintenance.

frontend/lib/views/settings/settings_view.dart

@@ -0,0 +1,72 @@
+import 'package:auto_gpt_flutter_client/viewmodels/settings_viewmodel.dart';
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+
+/// [SettingsView] displays a list of settings that the user can configure.
+/// It uses [SettingsViewModel] for state management and logic.
+class SettingsView extends StatelessWidget {
+  const SettingsView({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    // [ChangeNotifierProvider] provides an instance of [SettingsViewModel] to the widget tree.
+    return ChangeNotifierProvider(
+      create: (context) => SettingsViewModel(),
+      child: Scaffold(
+        appBar: AppBar(title: const Text('Settings')),
+        body: Consumer<SettingsViewModel>(
+          builder: (context, viewModel, child) {
+            // A list of settings is displayed using [ListView].
+            return ListView(
+              children: [
+                // Dark Mode Toggle
+                SwitchListTile(
+                  title: const Text('Dark Mode'),
+                  value: viewModel.isDarkModeEnabled,
+                  onChanged: viewModel.toggleDarkMode,
+                ),
+                // Developer Mode Toggle
+                SwitchListTile(
+                  title: const Text('Developer Mode'),
+                  value: viewModel.isDeveloperModeEnabled,
+                  onChanged: viewModel.toggleDeveloperMode,
+                ),
+                // Base URL Configuration
+                ListTile(
+                  title: const Text('Base URL'),
+                  subtitle: TextFormField(
+                    initialValue: viewModel.baseURL,
+                    onChanged: viewModel.updateBaseURL,
+                    decoration: const InputDecoration(
+                      hintText: 'Enter Base URL',
+                    ),
+                  ),
+                ),
+                // Continuous Mode Steps Configuration
+                ListTile(
+                  title: const Text('Continuous Mode Steps'),
+                  // User can increment or decrement the number of steps using '+' and '-' buttons.
+                  subtitle: Row(
+                    children: [
+                      IconButton(
+                        icon: const Icon(Icons.remove),
+                        onPressed: viewModel
+                            .decrementContinuousModeSteps, // Decrement the number of steps.
+                      ),
+                      Text('${viewModel.continuousModeSteps} Steps'),
+                      IconButton(
+                        icon: const Icon(Icons.add),
+                        onPressed: viewModel
+                            .incrementContinuousModeSteps, // Increment the number of steps.
+                      ),
+                    ],
+                  ),
+                ),
+              ],
+            );
+          },
+        ),
+      ),
+    );
+  }
+}