Asynchronously check for changes within remote change observer rather than enumerator, signal changes only when necessary

[claucambra]

No description provided.

[Copilot]

Pull Request Overview

This PR moves working set change detection out of Enumerator into RemoteChangeObserver, adds syncTime/deleted metadata flags, and updates tests to inject and validate against the database manager asynchronously.

• Add syncTime and deleted properties to item metadata and persist them in Realm.
• Implement pendingWorkingSetChanges in FilesDatabaseManager and simplify Enumerator to use it.
• Refactor RemoteChangeObserver to perform async working-set checks on notifications; update tests to pass and verify via injected dbManager.

Reviewed Changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
Sources/NextcloudFileProviderKit/Metadata/SendableItemMetadata.swift	Add syncTime and deleted fields and constructors.
Sources/NextcloudFileProviderKit/Metadata/RealmItemMetadata.swift	Persist new metadata fields.
Sources/NextcloudFileProviderKit/Metadata/ItemMetadata.swift	Extend protocol with new properties.
Sources/NextcloudFileProviderKit/Database/FilesDatabaseManager.swift	Mark deleted items instead of removing, add pendingWorkingSetChanges.
Sources/NextcloudFileProviderKit/Enumeration/RemoteChangeObserver.swift	Replace immediate notifications with async working-set checks.
Sources/NextcloudFileProviderKit/Enumeration/Enumerator.swift	Simplify change enumeration using DB-driven pending changes.
Tests/NextcloudFileProviderKitTests/RemoteChangeObserverTests.swift	Inject dbManager, update setup & assertions.
Tests/NextcloudFileProviderKitTests/FilesDatabaseManagerTests.swift	Adjust tests to validate deleted flag counts.
Tests/NextcloudFileProviderKitTests/EnumeratorTests.swift	Switch to using sync anchors and local DB queries.
Tests/Interface/MockChangeObserver.swift	Support new enumerateChanges(from:) signature.

Comments suppressed due to low confidence (4)

Tests/NextcloudFileProviderKitTests/RemoteChangeObserverTests.swift:164

• Remove leftover debugPrint(db) calls to reduce noise in test output.

        debugPrint(db)

Tests/NextcloudFileProviderKitTests/RemoteChangeObserverTests.swift:337

• Remove leftover debugPrint(db) calls to keep tests clean.

        debugPrint(db)

Tests/NextcloudFileProviderKitTests/RemoteChangeObserverTests.swift:462

• Remove leftover debugPrint(db) calls to reduce unnecessary output.

        debugPrint(db)

Tests/NextcloudFileProviderKitTests/FilesDatabaseManagerTests.swift:1260

• Remove the print(updatedIds) debug statement from the test; use assertions to verify behavior instead of printing.

        print(updatedIds)