UI freeze after adding new favorite

[dmpr0]

Description

A new issue was found during testing of #5006.

How to reproduce

• Import as Favorites – McDonalds (for free WiFi).gpx.zip
• Select any point on the map – Add to favorites
• Select McDonalds (for free WiFi) folder

Actual result

Freeze.mov

• UI Freeze

Expected result

• Working UI

Environment
OsmAnd Version:
iOS version: 26
Device model: iPhone 16 Pro Max

[DmitrySvetlichny]

This PR #5119 partially fixes the current issue.
But it still remains in the function

• (void)saveFiles:(NSArray<OAFavoriteGroup *> *)localGroups
  deleted:(NSArray<NSString *> *)deleted