feat: require Device to be Send+Sync

[roderickvd]

Also refactors the Stream assertions for Send + Sync bounds.

Fixes #435

[Copilot]

Pull request overview

Promotes Send + Sync from per-backend compile-time assertions to first-class supertrait bounds on DeviceTrait and StreamTrait, so that downstream code can pass Devices and Streams across thread boundaries unconditionally. Wrapper bounds in host::custom are simplified accordingly, the per-backend assert_stream_send!/assert_stream_sync! invocations are removed, and the macros themselves are deprecated. The audioworklet backend gains its own unsafe impl Send/Sync for Stream to satisfy the new bound.

Changes:

• Add Send + Sync supertrait bounds to DeviceTrait and StreamTrait; deprecate the now-redundant assertion macros.
• Drop redundant Send + Sync constraints from host::custom::{Host, Device, Stream} wrapper APIs and remove per-backend assert_stream_* invocations.
• Add unsafe impl Send/Sync for Stream in host::audioworklet; stop re-exporting Stream from host::coreaudio on macOS.

Reviewed changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/traits.rs	Adds Send + Sync supertraits and deprecates assert_stream_send!/assert_stream_sync!.
src/host/custom/mod.rs	Removes redundant Send + Sync / T::Stream: Send + Sync bounds now implied by traits.
src/host/audioworklet/mod.rs	Adds unsafe impl Send/Sync for Stream to satisfy the new supertrait.
src/host/coreaudio/mod.rs	Stops re-exporting Stream on macOS and removes the assertion macros.
src/host/{alsa,aaudio,asio,jack,null,wasapi,webaudio}/...	Removes now-redundant assert_stream_send!/assert_stream_sync! calls.
CHANGELOG.md	Notes the new bounds and macro deprecations.
UPGRADING.md	Adds a v0.18→v0.19 section describing the breaking change for custom hosts.

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Pull request overview

Copilot reviewed 14 out of 14 changed files in this pull request and generated 1 comment.

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Pull request overview

Copilot reviewed 14 out of 14 changed files in this pull request and generated 4 comments.

[Copilot]

Pull request overview

Copilot reviewed 14 out of 14 changed files in this pull request and generated 2 comments.

[Copilot]

Pull request overview

Copilot reviewed 14 out of 14 changed files in this pull request and generated 3 comments.

[Copilot]

Pull request overview

Copilot reviewed 16 out of 16 changed files in this pull request and generated 2 comments.