fix(audio): clear runtime access tracking on TCP listener teardown

[hikaps]

Summary

• Clear m_runtimeAccessSetForUid in cleanupTcpListenerIfLast() when the TCP listener config is removed, so SetupRuntimeAccess() re-runs on the next session start and recreates the PipeWire PulseAudio TCP listener

Problem

Audio routing broke after closing instances and starting a new session. The TCP listener config (50-couchplay.conf) was removed during teardown, but m_runtimeAccessSetForUid still contained the compositor UID. On the next launch, LaunchInstance() saw the UID in the set and skipped SetupRuntimeAccess() entirely — so the TCP listener was never recreated. Instances launched with PULSE_SERVER=tcp:127.0.0.1:4713 but nothing was listening.

Workaround was reinstalling the helper, which restarts the daemon and clears the in-memory set.

Testing

• Built and linked couchplay and couchplay-helper successfully
• Single-line fix in helper/CouchPlayHelper.cpp