Fix Server's missing opt-out of ring buffer

For now we still steal buffers from uvw.

In the future I'd like to change that, but it's still uvw
work-in-progress to support custom data allocators, and so for now we
still steal data buffers from uvw.

llarp/quic/server.hpp

@@ -12,7 +12,9 @@ namespace llarp::quic
     using stream_open_callback_t = std::function<bool(Stream& stream, uint16_t port)>;
 
     Server(EndpointBase& service_endpoint) : Endpoint{service_endpoint}
-    {}
+    {
+      default_stream_buffer_size = 0; // We don't currently use the endpoint ring buffer
+    }
 
     // Stream callback: takes the server, the (just-created) stream, and the connection port.
     // Returns true if the stream should be allowed or false to reject the stream.  The callback

llarp/quic/stream.hpp

@@ -175,7 +175,7 @@ namespace llarp::quic
 
     // Takes ownership of the given buffer pointer, queuing it to be sent after any existing buffers
     // and freed once fully acked.  You *must* have called `set_buffer_size(0)` (or set the
-    // endpoints default_stream_buffer_size to 0) in order to use this.
+    // endpoint's default_stream_buffer_size to 0) in order to use this.
     void
     append_buffer(const std::byte* buf, size_t length);