The old jdymusic CDN (e.g. m701/m801.music.126.net/.../jdymusic/obj/...)
intermittently drops connections from Node's HTTP stack — even with a
browser UA — while the same URL fetched via WinHTTP works. Newer paths
(/jd-musicrep-ts/, /ymusic/) do not have this restriction.
On Windows, dispatch /jdymusic/ URLs through `System.Net.WebClient` in
PowerShell into a temp file, then run ffmpeg against the file. Other
URLs and non-Windows platforms keep the direct ffmpeg + browser-UA path
from the previous commit. Also fix buildFfmpegArgs to omit HTTP-only
flags (-reconnect_*, -headers) when the input is a local file path —
new ffmpeg builds reject these as "Option not found".
stop() now also kills any in-flight PowerShell downloader and removes
the temp dir, so cancellation is clean.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
