Audio Cast reaches the marketplace after receiver access fixes

Audio Cast, submitted by yangkang5303 in omacom/omarchy-plugin-marketplace#11924, was published according to github-actions[bot]. The widget controls LAN audio casting through a separately installed Python CLI. Its receiver now starts with an empty source-IP allowlist, requiring owners to select trusted hosts before incoming connections are admitted.

Review progressed through access and revocation fixes. yangkang5303 replaced the internal TCP audio-server listener with the owner's private Unix socket. HANCORE-linux then identified a race in which an accepted connection could survive switching to restricted mode; yangkang5303 corrected registration to check the proxy's running state under the stop lock. HANCORE-linux confirmed that final fix and retention of the earlier corrections before publication. Manual CLI setup remains required, and the publication notice limits verification to the reviewed marketplace snapshot.