CmdPal: Add option to return to home automatically after a delay (#43551)

## Summary of the Pull Request

This PR replaces the Go home when activated setting with a new
Automatically return home option. This allows users to specify how long
the Command Palette should wait after being dismissed before
automatically returning to the home page. It also introduces migration
logic to transition from the old setting to the new one.

## Pictures? Pictures!

<img width="1337" height="762" alt="image"
src="https://github.com/user-attachments/assets/c649ef03-b3ee-40ba-ac67-485bc40efa73"
/>


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## PR Checklist

- [x] Closes: #43355 
<!-- - [ ] Closes: #yyy (add separate lines for additional resolved
issues) -->
- [ ] **Communication:** I've discussed this with core contributors
already. If the work hasn't been agreed, this work might be rejected
- [ ] **Tests:** Added/updated and all pass
- [ ] **Localization:** All end-user-facing strings can be localized
- [ ] **Dev docs:** Added/updated
- [ ] **New binaries:** Added on the required places
- [ ] [JSON for
signing](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ESRPSigning_core.json)
for new binaries
- [ ] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
for new binaries and localization folder
- [ ] [YML for CI
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ci/templates/build-powertoys-steps.yml)
for new test projects
- [ ] [YML for signed
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/release.yml)
- [ ] **Documentation updated:** If checked, please file a pull request
on [our docs
repo](https://github.com/MicrosoftDocs/windows-uwp/tree/docs/hub/powertoys)
and link it here: #xxx

<!-- Provide a more detailed description of the PR, other things fixed,
or any additional comments/features here -->
## Detailed Description of the Pull Request / Additional comments

<!-- Describe how you validated the behavior. Add automated tests
wherever possible, but list manual validation steps taken as well -->
## Validation Steps Performed

src/modules/cmdpal/Microsoft.CmdPal.UI.ViewModels/SettingsModel.cs

@@ -6,7 +6,9 @@ using System.Diagnostics;
 using System.Text.Json;
 using System.Text.Json.Nodes;
 using System.Text.Json.Serialization;
+using System.Text.Json.Serialization.Metadata;
 using CommunityToolkit.Mvvm.ComponentModel;
+using ManagedCommon;
 using Microsoft.CmdPal.UI.ViewModels.Settings;
 using Microsoft.CommandPalette.Extensions.Toolkit;
 using Windows.Foundation;
@@ -15,6 +17,8 @@ namespace Microsoft.CmdPal.UI.ViewModels;
 
 public partial class SettingsModel : ObservableObject
 {
+    private const string DeprecatedHotkeyGoesHomeKey = "HotkeyGoesHome";
+
     [JsonIgnore]
     public static readonly string FilePath;
 
@@ -30,8 +34,6 @@ public partial class SettingsModel : ObservableObject
 
     public bool ShowAppDetails { get; set; }
 
-    public bool HotkeyGoesHome { get; set; }
-
     public bool BackspaceGoesBack { get; set; }
 
     public bool SingleClickActivates { get; set; }
@@ -56,6 +58,8 @@ public partial class SettingsModel : ObservableObject
 
     public WindowPosition? LastWindowPosition { get; set; }
 
+    public TimeSpan AutoGoHomeInterval { get; set; } = Timeout.InfiniteTimeSpan;
+
     // END SETTINGS
     ///////////////////////////////////////////////////////////////////////////
 
@@ -98,12 +102,29 @@ public partial class SettingsModel : ObservableObject
         {
             // Read the JSON content from the file
             var jsonContent = File.ReadAllText(FilePath);
+            var loaded = JsonSerializer.Deserialize<SettingsModel>(jsonContent, JsonSerializationContext.Default.SettingsModel) ?? new();
 
-            var loaded = JsonSerializer.Deserialize<SettingsModel>(jsonContent, JsonSerializationContext.Default.SettingsModel);
+            var migratedAny = false;
+            try
+            {
+                if (JsonNode.Parse(jsonContent) is JsonObject root)
+                {
+                    migratedAny |= ApplyMigrations(root, loaded);
+                }
+            }
+            catch (Exception ex)
+            {
+                Debug.WriteLine($"Migration check failed: {ex}");
+            }
 
-            Debug.WriteLine(loaded is not null ? "Loaded settings file" : "Failed to parse");
+            Debug.WriteLine("Loaded settings file");
 
-            return loaded ?? new();
+            if (migratedAny)
+            {
+                SaveSettings(loaded);
+            }
+
+            return loaded;
         }
         catch (Exception ex)
         {
@@ -113,6 +134,51 @@ public partial class SettingsModel : ObservableObject
         return new();
     }
 
+    private static bool ApplyMigrations(JsonObject root, SettingsModel model)
+    {
+        var migrated = false;
+
+        // Migration #1: HotkeyGoesHome (bool) -> AutoGoHomeInterval (TimeSpan)
+        // The old 'HotkeyGoesHome' boolean indicated whether the "go home" action should happen immediately (true) or never (false).
+        // The new 'AutoGoHomeInterval' uses a TimeSpan: 'TimeSpan.Zero' means immediate, 'Timeout.InfiniteTimeSpan' means never.
+        migrated |= TryMigrate(
+            "Migration #1: HotkeyGoesHome (bool) -> AutoGoHomeInterval (TimeSpan)",
+            root,
+            model,
+            nameof(AutoGoHomeInterval),
+            DeprecatedHotkeyGoesHomeKey,
+            (settingsModel, goesHome) => settingsModel.AutoGoHomeInterval = goesHome ? TimeSpan.Zero : Timeout.InfiniteTimeSpan,
+            JsonSerializationContext.Default.Boolean);
+
+        return migrated;
+    }
+
+    private static bool TryMigrate<T>(string migrationName, JsonObject root, SettingsModel model, string newKey, string oldKey, Action<SettingsModel, T> apply, JsonTypeInfo<T> jsonTypeInfo)
+    {
+        try
+        {
+            // If new key already present, skip migration
+            if (root.ContainsKey(newKey) && root[newKey] is not null)
+            {
+                return false;
+            }
+
+            // If old key present, try to deserialize and apply
+            if (root.TryGetPropertyValue(oldKey, out var oldNode) && oldNode is not null)
+            {
+                var value = oldNode.Deserialize<T>(jsonTypeInfo);
+                apply(model, value!);
+                return true;
+            }
+        }
+        catch (Exception ex)
+        {
+            Logger.LogError($"Error during migration {migrationName}.", ex);
+        }
+
+        return false;
+    }
+
     public static void SaveSettings(SettingsModel model)
     {
         if (string.IsNullOrEmpty(FilePath))
@@ -139,6 +205,9 @@ public partial class SettingsModel : ObservableObject
                         savedSettings[item.Key] = item.Value?.DeepClone();
                     }
 
+                    // Remove deprecated keys
+                    savedSettings.Remove(DeprecatedHotkeyGoesHomeKey);
+
                     var serialized = savedSettings.ToJsonString(JsonSerializationContext.Default.Options);
                     File.WriteAllText(FilePath, serialized);
 

src/modules/cmdpal/Microsoft.CmdPal.UI.ViewModels/SettingsViewModel.cs

@@ -11,6 +11,19 @@ namespace Microsoft.CmdPal.UI.ViewModels;
 
 public partial class SettingsViewModel : INotifyPropertyChanged
 {
+    private static readonly List<TimeSpan> AutoGoHomeIntervals =
+    [
+        Timeout.InfiniteTimeSpan,
+        TimeSpan.Zero,
+        TimeSpan.FromSeconds(10),
+        TimeSpan.FromSeconds(20),
+        TimeSpan.FromSeconds(30),
+        TimeSpan.FromSeconds(60),
+        TimeSpan.FromSeconds(90),
+        TimeSpan.FromSeconds(120),
+        TimeSpan.FromSeconds(180),
+    ];
+
     private readonly SettingsModel _settings;
     private readonly IServiceProvider _serviceProvider;
 
@@ -58,16 +71,6 @@ public partial class SettingsViewModel : INotifyPropertyChanged
         }
     }
 
-    public bool HotkeyGoesHome
-    {
-        get => _settings.HotkeyGoesHome;
-        set
-        {
-            _settings.HotkeyGoesHome = value;
-            Save();
-        }
-    }
-
     public bool BackspaceGoesBack
     {
         get => _settings.BackspaceGoesBack;
@@ -138,6 +141,25 @@ public partial class SettingsViewModel : INotifyPropertyChanged
         }
     }
 
+    public int AutoGoBackIntervalIndex
+    {
+        get
+        {
+            var index = AutoGoHomeIntervals.IndexOf(_settings.AutoGoHomeInterval);
+            return index >= 0 ? index : 0;
+        }
+
+        set
+        {
+            if (value >= 0 && value < AutoGoHomeIntervals.Count)
+            {
+                _settings.AutoGoHomeInterval = AutoGoHomeIntervals[value];
+            }
+
+            Save();
+        }
+    }
+
     public ObservableCollection<ProviderSettingsViewModel> CommandProviders { get; } = [];
 
     public SettingsExtensionsViewModel Extensions { get; }