* Initial implementation of migration between memory heaps
- Missing OOM handling
- Missing `_map` data safety when remapping
- Copy may not have completed yet (needs some kind of fence)
- Map may be unmapped before it is done being used. (needs scoped access)
- SSBO accesses are all "writes" - maybe pass info in another way.
- Missing keeping map type when resizing buffers (should this be done?)
* Ensure migrated data is in place before flushing.
* Fix issue where old waitable would be signalled.
- There is a real issue where existing Auto<> references need to be replaced.
* Swap bound Auto<> instances when swapping buffer backing
* Fix conversion buffers
* Don't try move buffers if the host has shared memory.
* Make GPU methods return PinnedSpan with scope
* Storage Hint
* Fix stupidity
* Fix rebase
* Tweak rules
Attempt to sidestep BOTW slowdown
* Remove line
* Migrate only when command buffers flush
* Change backing swap log to debug
* Address some feedback
* Disallow backing swap when the flush lock is held by the current thread
* Make PinnedSpan from ReadOnlySpan explicitly unsafe
* Fix some small issues
- Index buffer swap fixed
- Allocate DeviceLocal buffers using a separate block list to images.
* Remove alternative flags
* Address feedback
