Need way to hook initialization for given PInvokes

[JeremyKuhne]

Is your feature request related to a problem? Please describe.

Using a GDI+ API needs to have GDI+ initialized. In System.Drawing this was accomplished in the static constructor for the manually written PInvokes. Moving to CSWin32 we can still create a static constructor on the partial to do this, but not for a shared assembly where we only want to start GDI+ when we know we're going to use it (some usages of the shared assembly do not use GDI+).

Describe the solution you'd like

The ability to specify the static class a method goes to? Could leverage this for other organization?

GdipBitmapLockBits, class:GdipPInvoke

Describe alternatives you've considered

• Creating a separate assembly for every case we have like this
• Allowing specifying some sort of partial static initialization method in the NativeMethods.txt

Additional context

Our first regression in .NET 9 with System.Drawing after moving to CsWin32 was around this.