stream_op cleanup: transport changes

src/core/transport/byte_stream.c

src/core/transport/byte_stream.h

src/core/transport/chttp2/frame_data.c

src/core/transport/chttp2/frame_data.h

src/core/transport/chttp2/frame_window_update.c

src/core/transport/chttp2/hpack_encoder.c

src/core/transport/chttp2/hpack_encoder.h

src/core/transport/chttp2/hpack_parser.c

src/core/transport/chttp2/incoming_metadata.c

src/core/transport/chttp2/incoming_metadata.h

src/core/transport/chttp2/internal.h

src/core/transport/chttp2/parsing.c

src/core/transport/chttp2/stream_lists.c

src/core/transport/chttp2/writing.c

src/core/transport/chttp2_transport.c

src/core/transport/metadata.c

src/core/transport/metadata_batch.c

src/core/transport/metadata_batch.h

src/core/transport/transport.c

src/core/transport/transport.h