Fix undo delegate witness matching

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: johankool

Examples/Reminders/RemindersApp.swift

@@ -89,7 +89,7 @@ class RemindersSyncEngineDelegate: SyncEngineDelegate {
 
 @MainActor
 @Observable
-final class RemindersUndoManagerDelegate: UndoManagerDelegate {
+final class RemindersUndoManagerDelegate: SQLiteData.UndoManagerDelegate {
   struct ConfirmationRequest: Identifiable {
     let action: UndoAction
     let group: UndoGroup
@@ -135,7 +135,7 @@ final class RemindersUndoManagerDelegate: UndoManagerDelegate {
     _ undoManager: SQLiteData.UndoManager,
     willPerform action: UndoAction,
     for group: UndoGroup,
-    performAction: @Sendable () async throws -> Void
+    performAction: @isolated(any) @Sendable () async throws -> Void
   ) async throws {
     guard shouldConfirm(for: group) else {
       try await performAction()

Sources/SQLiteData/Undo/UndoManagerDelegate.swift

@@ -3,8 +3,6 @@
 /// The delegate can present a confirmation prompt, or perform any async work, before calling
 /// `performAction` to commit the operation.  If `performAction` is not called, the operation is
 /// cancelled and the undo/redo stacks remain unchanged.
-///
-/// The default implementation performs the action immediately without any confirmation.
 public protocol UndoManagerDelegate: AnyObject, Sendable {
   /// Called before the undo manager performs an undo or redo operation.
   ///
@@ -13,24 +11,10 @@ public protocol UndoManagerDelegate: AnyObject, Sendable {
   ///   - action: Whether this is an undo or redo.
   ///   - group: The group of changes that will be undone or redone.
   ///   - performAction: Call this to commit the operation.  Omitting this call cancels it.
-  @MainActor
   func undoManager(
     _ undoManager: SQLiteData.UndoManager,
     willPerform action: UndoAction,
     for group: UndoGroup,
     performAction: @Sendable () async throws -> Void
   ) async throws
 }
-
-extension UndoManagerDelegate {
-  /// Default implementation: immediately performs the action without confirmation.
-  @MainActor
-  public func undoManager(
-    _ undoManager: SQLiteData.UndoManager,
-    willPerform action: UndoAction,
-    for group: UndoGroup,
-    performAction: @Sendable () async throws -> Void
-  ) async throws {
-    try await performAction()
-  }
-}

Tests/SQLiteDataTests/UndoTests/UndoManagerTests.swift

@@ -396,7 +396,6 @@ extension DatabaseWriter where Self == DatabaseQueue {
   }
 
   @Test func delegateCancel() async throws {
-    @MainActor
     final class CancelDelegate: UndoManagerDelegate {
       func undoManager(
         _ undoManager: SQLiteData.UndoManager,
@@ -433,7 +432,6 @@ extension DatabaseWriter where Self == DatabaseQueue {
     }
     let capture = MetadataCapture()
 
-    @MainActor
     final class MetadataDelegate: UndoManagerDelegate, @unchecked Sendable {
       let capture: MetadataCapture
       init(_ capture: MetadataCapture) { self.capture = capture }
@@ -475,7 +473,6 @@ extension DatabaseWriter where Self == DatabaseQueue {
     }
     let capture = ActionCapture()
 
-    @MainActor
     final class ActionDelegate: UndoManagerDelegate, @unchecked Sendable {
       let capture: ActionCapture
       init(_ capture: ActionCapture) { self.capture = capture }