iidx: camera hook improvements (#841)

## Link to GitHub Issue or related Pull Request, if one exists
#201

## Description of change

- Adds MJPEG camera support using Media Foundation decoding.
- Moves camera capture to asynchronous Source Reader callbacks.
- Supports native NV12 and YUY2 capture, preferring target-sized native
formats over MJPEG when possible.
- Improves capture and rendering performance through callback-paced
reads, bulk frame uploads, optimized row-based flips, and lazy
allocation of flip textures.
- Makes runtime media-type changes interrupt pending reads and safely
flush and reconfigure the Source Reader.
- Improves automatic mode selection based on aspect ratio, proximity to
1280x720, frame rate, and capture format.
- Hardens camera shutdown, flush handling, media-type changes, and
repeated capture failures.

## Testing
Tested with two cameras in tdj

src/spice2x/games/iidx/mf_wrappers.h

@@ -12,6 +12,9 @@ namespace games::iidx {
         _Out_ IMFAttributes** ppMFAttributes,
         _In_ UINT32 cInitialSize);
 
+    HRESULT WrappedMFCreateMediaType (
+        _Out_ IMFMediaType** ppMFType);
+
     HRESULT WrappedMFEnumDeviceSources (
         _In_ IMFAttributes* pAttributes,
         _Outptr_result_buffer_(*pcSourceActivate) IMFActivate*** pppSourceActivate,