MOQT Message formats from draft-02.

Also totally refactored the API for sending Objects. Now that the spec clarifies the stream mapping, applications simply indicate the forwarding preference, and MoqtSession does all the stream management (except that the application indicates when the stream is done.)

Not in production.

PiperOrigin-RevId: 603743999
diff --git a/build/source_list.bzl b/build/source_list.bzl
index 9431ce4..88ba579 100644
--- a/build/source_list.bzl
+++ b/build/source_list.bzl
@@ -1497,6 +1497,7 @@
     "quic/moqt/moqt_parser_test.cc",
     "quic/moqt/moqt_session.cc",
     "quic/moqt/moqt_session_test.cc",
+    "quic/moqt/moqt_subscribe_windows.cc",
     "quic/moqt/moqt_subscribe_windows_test.cc",
     "quic/moqt/moqt_track_test.cc",
     "quic/moqt/tools/chat_client_bin.cc",