CmdPal: Migrate bookmarks manually (#42814)

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fix/what does it change/how was it tested (even manually, if necessary)?
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## Summary of the Pull Request

This PR fixes the migration of bookmarks from versions prior to 0.95,
resolving an issue where hotkeys and aliases wouldn’t persist on
bookmarks created with Command Palette 0.94 or earlier.

It removes ID auto-fixing from `BookmarkData` in favor of an explicit
migration step handled by `BookmarkManager`.

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## PR Checklist

- [x] Closes: #42796
- [ ] **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
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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

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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/Tests/Microsoft.CmdPal.Ext.Bookmarks.UnitTests/BookmarkManagerTests.cs

@@ -186,4 +186,48 @@ public class BookmarkManagerTests
         Assert.AreEqual("D:\\UpdatedPath", updatedBookmark.Bookmark);
         Assert.IsTrue(bookmarkUpdatedEventFired);
     }
+
+    [TestMethod]
+    public void BookmarkManager_LegacyData_IdsArePersistedAcrossLoads()
+    {
+        // Arrange
+        const string json = """
+                            {
+                                "Data": 
+                                [
+                                    { "Name": "C:\\","Bookmark": "C:\\" },
+                                    { "Name": "Bing.com","Bookmark": "https://bing.com" }
+                                ]
+                            }
+                            """;
+
+        var dataSource = new MockBookmarkDataSource(json);
+
+        // First load: IDs should be generated for legacy entries
+        var manager1 = new BookmarksManager(dataSource);
+        var firstLoad = manager1.Bookmarks.ToList();
+        Assert.AreEqual(2, firstLoad.Count);
+        Assert.AreNotEqual(Guid.Empty, firstLoad[0].Id);
+        Assert.AreNotEqual(Guid.Empty, firstLoad[1].Id);
+
+        // Keep a name->id map to be insensitive to ordering
+        var firstIdsByName = firstLoad.ToDictionary(b => b.Name, b => b.Id);
+
+        // Wait deterministically for async persistence to complete
+        var wasSaved = dataSource.WaitForSave(1, 5000);
+        Assert.IsTrue(wasSaved, "Data was not saved within the expected time.");
+
+        // Second load: should read back the same IDs from persisted data
+        var manager2 = new BookmarksManager(dataSource);
+        var secondLoad = manager2.Bookmarks.ToList();
+        Assert.AreEqual(2, secondLoad.Count);
+
+        var secondIdsByName = secondLoad.ToDictionary(b => b.Name, b => b.Id);
+
+        foreach (var kvp in firstIdsByName)
+        {
+            Assert.IsTrue(secondIdsByName.ContainsKey(kvp.Key), $"Missing bookmark '{kvp.Key}' after reload.");
+            Assert.AreEqual(kvp.Value, secondIdsByName[kvp.Key], $"Bookmark '{kvp.Key}' upgraded ID was not persisted across loads.");
+        }
+    }
 }

src/modules/cmdpal/Tests/Microsoft.CmdPal.Ext.Bookmarks.UnitTests/MockBookmarkDataSource.cs

@@ -2,6 +2,8 @@
 // The Microsoft Corporation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
+using System.Threading;
 using Microsoft.CmdPal.Ext.Bookmarks.Persistence;
 
 namespace Microsoft.CmdPal.Ext.Bookmarks.UnitTests;
@@ -9,6 +11,7 @@ namespace Microsoft.CmdPal.Ext.Bookmarks.UnitTests;
 internal sealed class MockBookmarkDataSource : IBookmarkDataSource
 {
     private string _jsonData;
+    private int _saveCount;
 
     public MockBookmarkDataSource(string initialJsonData = "[]")
     {
@@ -23,5 +26,26 @@ internal sealed class MockBookmarkDataSource : IBookmarkDataSource
     public void SaveBookmarkData(string jsonData)
     {
         _jsonData = jsonData;
+        Interlocked.Increment(ref _saveCount);
+    }
+
+    public int SaveCount => Volatile.Read(ref _saveCount);
+
+    // Waits until at least expectedMinSaves have occurred or the timeout elapses.
+    // Returns true if the condition was met, false on timeout.
+    public bool WaitForSave(int expectedMinSaves = 1, int timeoutMs = 2000)
+    {
+        var start = Environment.TickCount;
+        while (Volatile.Read(ref _saveCount) < expectedMinSaves)
+        {
+            if (Environment.TickCount - start > timeoutMs)
+            {
+                return false;
+            }
+
+            Thread.Sleep(50);
+        }
+
+        return true;
     }
 }

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Bookmark/BookmarksManager.cs

@@ -103,7 +103,33 @@ internal sealed partial class BookmarksManager : IDisposable, IBookmarksManager
         try
         {
             var jsonData = _dataSource.GetBookmarkData();
-            _bookmarksData = _parser.ParseBookmarks(jsonData);
+            var bookmarksData = _parser.ParseBookmarks(jsonData);
+
+            // Upgrade old bookmarks if necessary
+            // Pre .95 versions did not assign IDs to bookmarks
+            var upgraded = false;
+            for (var index = 0; index < bookmarksData.Data.Count; index++)
+            {
+                var bookmark = bookmarksData.Data[index];
+                if (bookmark.Id == Guid.Empty)
+                {
+                    bookmarksData.Data[index] = bookmark with { Id = Guid.NewGuid() };
+                    upgraded = true;
+                }
+            }
+
+            lock (_lock)
+            {
+                _bookmarksData = bookmarksData;
+            }
+
+            // LOAD BEARING: Save upgraded data back to file
+            // This ensures that old bookmarks are not repeatedly upgraded on each load,
+            // as the hotkeys and aliases are tied to the generated bookmark IDs.
+            if (upgraded)
+            {
+                _ = SaveChangesAsync();
+            }
         }
         catch (Exception ex)
         {

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Bookmark/Persistence/BookmarkData.cs

@@ -19,7 +19,7 @@ public sealed record BookmarkData
     [SetsRequiredMembers]
     public BookmarkData(Guid id, string? name, string? bookmark)
     {
-        Id = id == Guid.Empty ? Guid.NewGuid() : id;
+        Id = id;
         Name = name ?? string.Empty;
         Bookmark = bookmark ?? string.Empty;
     }