Network stream filters: add STREAM_GET_PTS_DELAY

Any network (HTTP) stream filter, and more generally any stream filter that would get its data not from its source stream, should specify a PTS delay according to the actual data source. This requires a STREAM_GET_PTS_DELAY control.

Currently, the PTS delay is obtained from the access. This only works if the PTS delay policy of the access matches.

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information