Swift Compiler Error: Explicit Capture of 'self' Required in Visualizer.swift

After updating Flutter to the latest version, the livekit_client package (v2.3.2) fails to build on iOS. The following Swift compiler error occurs:

```
Reference to property 'eventSink' in closure requires explicit use of 'self' to make capture semantics explicit
/Users/dpl-ashif/.pub-cache/hosted/pub.dev/livekit_client-2.3.2/ios/Classes/Visualizer.swift:90:12

```