Introduce a dedicated utility that probes browser support for AAC/WebCodecs audio settings instead of assuming a single hardcoded configuration (`mp4a.40.2`, 192 kbps, stereo, 44.1 kHz). This file should centralize support detection and fallback selection so ChromeOS/Chrome variants that reject the current config can still export with audio.
Affected files: audio-codec-support.ts
Signed-off-by: ChinhLee <76194645+chinhkrb113@users.noreply.github.com>