fix: add StreamTrait impl for all remaining backends

Add missing StreamTrait implementations for platform-specific backends that
couldn't be tested on macOS:
- aaudio (Android)
- asio (Windows)
- wasapi (Windows)
- alsa (Linux)
- null (WASI)

Each implementation delegates play/pause to the inner UnsupportedDuplexStream.

Author: gulbrand

src/host/aaudio/mod.rs

@@ -117,6 +117,16 @@ pub struct Device(Option<AudioDeviceInfo>);
 
 pub struct DuplexStream(pub crate::duplex::UnsupportedDuplexStream);
 
+impl StreamTrait for DuplexStream {
+    fn play(&self) -> Result<(), PlayStreamError> {
+        StreamTrait::play(&self.0)
+    }
+
+    fn pause(&self) -> Result<(), PauseStreamError> {
+        StreamTrait::pause(&self.0)
+    }
+}
+
 /// Stream wraps AudioStream in Arc<Mutex<>> to provide Send + Sync semantics.
 ///
 /// While the underlying ndk::audio::AudioStream is neither Send nor Sync in ndk 0.9.0

src/host/alsa/mod.rs

@@ -90,6 +90,16 @@ const LIBC_ENOTSUPP: libc::c_int = 524;
 
 pub struct DuplexStream(pub crate::duplex::UnsupportedDuplexStream);
 
+impl crate::traits::StreamTrait for DuplexStream {
+    fn play(&self) -> Result<(), crate::PlayStreamError> {
+        crate::traits::StreamTrait::play(&self.0)
+    }
+
+    fn pause(&self) -> Result<(), crate::PauseStreamError> {
+        crate::traits::StreamTrait::pause(&self.0)
+    }
+}
+
 /// The default Linux and BSD host type.
 #[derive(Debug, Clone)]
 pub struct Host {

src/host/asio/mod.rs

@@ -23,6 +23,16 @@ mod stream;
 
 pub struct DuplexStream(pub crate::duplex::UnsupportedDuplexStream);
 
+impl StreamTrait for DuplexStream {
+    fn play(&self) -> Result<(), PlayStreamError> {
+        StreamTrait::play(&self.0)
+    }
+
+    fn pause(&self) -> Result<(), PauseStreamError> {
+        StreamTrait::pause(&self.0)
+    }
+}
+
 /// Global ASIO instance shared across all Host instances.
 ///
 /// ASIO only supports loading a single driver at a time globally, so all Host instances

src/host/null/mod.rs

@@ -29,6 +29,16 @@ crate::assert_stream_sync!(Stream);
 
 pub struct DuplexStream(pub crate::duplex::UnsupportedDuplexStream);
 
+impl StreamTrait for DuplexStream {
+    fn play(&self) -> Result<(), PlayStreamError> {
+        StreamTrait::play(&self.0)
+    }
+
+    fn pause(&self) -> Result<(), PauseStreamError> {
+        StreamTrait::pause(&self.0)
+    }
+}
+
 #[derive(Clone)]
 pub struct SupportedInputConfigs;
 #[derive(Clone)]

src/host/wasapi/mod.rs

@@ -17,6 +17,16 @@ use windows::Win32::Media::Audio;
 
 pub struct DuplexStream(pub crate::duplex::UnsupportedDuplexStream);
 
+impl StreamTrait for DuplexStream {
+    fn play(&self) -> Result<(), crate::PlayStreamError> {
+        StreamTrait::play(&self.0)
+    }
+
+    fn pause(&self) -> Result<(), crate::PauseStreamError> {
+        StreamTrait::pause(&self.0)
+    }
+}
+
 mod com;
 mod device;
 mod stream;