SDL3/CategoryAudio: Added simplified audio notes.

Live page is here: https://wiki.libsdl.org/SDL3/CategoryAudio

SDL3/CategoryAudio.md

@@ -11,9 +11,8 @@ time, in any supported format, and output it as needed in any other format,
 even if the data format changes on either side halfway through.
 
 An app opens an audio device and binds any number of audio streams to it,
-feeding more data to the streams as available. When the devices needs more
-data, it will pull it from all bound streams and mix them together for
-playback.
+feeding more data to the streams as available. When the device needs more data, it
+will pull it from all bound streams and mix them together for playback.
 
 Audio streams can also use an app-provided callback to supply data
 on-demand, which maps pretty closely to the SDL2 audio model.
@@ -45,6 +44,21 @@ migrate the logical devices to the correct physical device seamlessly and
 keep playing; the app doesn't even have to know it happened if it doesn't
 want to.
 
+## Simplified audio
+
+As a simplified model for when a single source of audio is all that's needed, an 
+app can use [SDL_OpenAudioDeviceStream](SDL_OpenAudioDeviceStream), which is a
+single function to open an audio device, create an audio stream, bind that stream
+to the newly-opened device, and (optionally) provide a callback for obtaining
+audio data. When using this function, the primary interface is the
+[SDL_AudioStream](SDL_AudioStream) and the device handle is mostly hidden away;
+destroying a stream created through this function will also close the device,
+stream bindings cannot be changed, etc. One other quirk of this is that the 
+device is started in a _paused_ state and must be explicitly resumed; this is
+partially to offer a clean migration for SDL2 apps and partially because the app
+might have to do more setup before playback begins; in the non-simplified form,
+nothing will play until a stream is bound to a device, so they start _unpaused_.
+
 ## Channel layouts
 
 Audio data passing through SDL is uncompressed PCM data, interleaved. One