Do not use dynamic types anymore. The reason is that it's difficult:
- to maintain a shared type database over a network.
- the extra overhead when translating between processes and for
maintaining the translation tables.
- race conditions in translating in RT-threads, this is a problem
because we want to make event streams.
We now have simple enums with types and extension points for all
types. This is also nicer to use in general.
We don't need the mapper anymore or pass strings around as types.
There is a parallel type info system to get more info about ids and
enums and their hierarchy. It can also be used for debugging.
Simplify the stream API. make just 2 methods to queue and dequeue
buffers. Make just one callback when new buffers can be dequeued.
Add support for driver nodes such as the video-src.
Pass a pw_buffer structure to add/remove_buffer and make it possible
to attach metadata to it. This makes it a lot easier to implement
the gstreamer pipewire pool.
Call the stream process function from the main loop and use a lockfree
ringbuffer to pass buffers between the threads. Make it possible to
also call process from the RT thread.
unmap the buffer data when needed.
The listeners are generally useful in spa, move it there and rename
to hooks. Implement loop hooks with it.
Fix some cleanup issues in stream and remote
Remove signals.
Rename callbacks -> events, use listeners to listen for events.
Callbacks are still used in spa for things you can listen to only
once.
