[Architecture] Implement gapless FLAC audio buffer preload queue for smooth track transitions #8

Overview

Implement an asynchronous pre-caching mechanism that decodes the first 500ms of the subsequent track while the current track is reaching completion.

Tasks

• Integrate double-buffered audio track feeder.
• Ensure zero gap clicks or sample drops on FLAC lossless streams.
• Benchmarked memory footprint below 35MB overhead.