Add buffer size attribute/struct for FindFirstFileEx family

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The FindFirstFileEx family of functions (FindFirstFileExW, FindFirstFileExA, FindFirstFileExFromAppW, FindFirstFileTransactedA, FindFirstFileTransactedW) all have an out ```void* lpFindFileData``` parameter where the size and structure of the buffer written is documented to be based on the ```fInfoLevelId``` enum parameter (documented at https://learn.microsoft.com/en-us/windows/win32/api/minwinbase/ne-minwinbase-findex_info_levels). However, both values of that enum have the same result of writing a WIN32_FIND_DATA (there are A and W versions). The SAL annotations also acknowledge this -- for example FindFirstFileExW is annotated ```_Out_writes_bytes_(sizeof(WIN32_FIND_DATAW)) LPVOID lpFindFileData```.

Ideally the type for ```lpFindFileData``` could change to ```WIN32_FIND_DATA``` for the greatest clarity, but if not, annotating it with ```NativeArrayInfoAttribute``` would help with marshaling.

Start by reviewing the metadata definitions for FindFirstFileExW/A, FindFirstFileExFromAppW, and FindFirstFileTransactedA/W, along with the NativeArrayInfoAttribute handling. Compare the documented fInfoLevelId buffer requirements with the existing generated representation; done means the metadata clearly describes the WIN32_FIND_DATA buffer size and structure.

Written by the indexing model from the issue text.