Fix Boost audio downloads using direct MPD lookup

[brealorg]

This fixes Boost for Reddit audio retrieval for v.redd.it video downloads/shares.

The previous implementation tried to resolve the Reddit post JSON by requesting the v.redd.it base URL, following the redirected URL, and then appending /.json. Reddit currently returns a non-JSON response in this path for some videos, causing:

Failed to retrieve audio:
com.fasterxml.jackson.core.JsonParseException:
Unexpected character ('<' (code 60))

Since the intercepted request already contains the v.redd.it media base URL, this change avoids the brittle Reddit JSON lookup and fetches the DASH manifest directly from:

https://v.redd.it//DASHPlaylist.mpd

The existing MPD parser is then used to resolve the audio BaseURL.

This also fixes the parser’s bandwidth selection logic by updating maxBandwidth when a better audio representation is found, and filters the selection so it only considers audio representations.

Tested locally with Boost 1.12.12 patched through Morphe using a local Patcheddit .mpp bundle.

Before:

• Boost playback had audio.
• Sharing/downloading showed Failed to retrieve audio.
• Logcat showed JsonParseException: Unexpected character '<'.

After:

• Sharing/downloading works with audio.
• No Failed to retrieve audio toast.

[Tenny131]

I tested it and it works without issues, thanks for your efforts!