Bias the QUIC connection writer's drain loop toward higher-priority
streams so moq-lite group streams with newer (higher) sequence numbers
drain ahead of older ones under congestion. Implements the T11.3
follow-up flagged in nestsClient/plans/2026-05-06-stream-priority-
followup.md (now removed).
QuicStream gets a `@Volatile var priority: Int = 0`. The writer's
streamsView iteration is replaced by a stable sortedByDescending pass
so same-priority streams keep their existing rotating-start round
robin while higher-priority tiers always drain first.
WebTransportWriteStream gains a `setPriority(Int)` hook; the QUIC-
backed adapter forwards to the underlying QuicStream, while the
in-memory test fakes treat it as a no-op. MoqLiteSession.openGroupStream
calls `uni.setPriority(sequence)` (saturating to Int.MAX_VALUE) to
mirror moq-rs's `Publisher::serve_group`.
Tests: a new InMemoryQuicPipe.decryptClientApplicationFrames helper
walks past coalesced long-header packets to surface 1-RTT frames,
which lets QuicConnectionWriterTest assert that the higher-priority
stream's StreamFrame lands first inside a single drained packet.
https://claude.ai/code/session_01KWdr4RjVvyYZfEuPVaQfUa
Claude
f1034b1f53