chore: Add @MainActor annotations for Swift 6 concurrency [Phase 2]

[iHackSubhodip]

Summary

• Continues Swift 6 concurrency migration by adding @MainActor annotations to delegate implementations and UI-related classes
• Fixes MainActor isolation warnings in 4 view controllers
• Ensures thread safety for UI operations in delegate methods

Changes Made

• AnimatedCurrentLocationViewController: Added @MainActor to CLLocationManagerDelegate extension
• CustomIndoorViewController: Added @MainActor to GMSIndoorDisplayDelegate extension
• DataDrivenStylingBasicViewController: Added @MainActor to SliderControls class and addSliderAndLabel static method
• DataDrivenStylingSearchViewController: Added @MainActor to PlaceLookupController class

Test Plan

• Verify no Swift 6 concurrency warnings in modified files
• Ensure existing functionality remains unchanged
• Test delegate methods respond correctly to user interactions
• Confirm UI updates happen on main thread