Fix yamux stream handle split

[driftluo]

When self.recv_frames_wake(cx) is called on the write side, it passes the write side's context/waker to the channel. This overwrites the read side's waker, preventing the message from waking up and causing messages to be unreadable. This PR fixes this overwriting error and provides several test cases to ensure correct behavior.

Just so you know, this problem only manifests when the StreamHandle is split; when it's not split, reading and writing share a single waker without issue.

[Copilot]

Pull request overview

Fixes a deadlock in yamux::StreamHandle when the handle is split into read/write halves: the write side previously polled frame_receiver with the write task’s waker, overwriting the read side’s waker and preventing reads from being awakened.

Changes:

• Refactors frame draining on the write side to use a non-waker-registering path (try_recv_frames) to avoid overwriting the read task’s waker.
• Adds deterministic regression tests in yamux/src/stream.rs validating correct waker behavior across split read/write polling.
• Adds tentacle integration tests (behind unstable) exercising first-message and multi-message spawn flows; bumps socket2 dependency.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
yamux/src/stream.rs	Introduces try_recv_frames and adjusts waker registration/wake-up behavior; adds multiple regression tests.
tentacle/tests/test_spawn_first_message.rs	Adds integration tests covering the spawn-based first message and sustained bidirectional messaging paths.
tentacle/Cargo.toml	Updates socket2 from 0.5.0 to 0.6.0.

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