PictView thumbnails not rendered for long paths (>260 chars)

[0xeb]

Split from #24. Image thumbnails are not rendered for files with paths >260 chars on UNC/WSL shares.

Root cause: PictView plugin likely uses CreateFileW/GetFileAttributesW without \?\ prefix, same pattern fixed in #24 for the internal viewer.

Deferred until PictView is added to the CMake build. The fix approach is the same: replace raw Win32 calls with SalLPCreateFile/SalLPGetFileAttributes from widepath.h.

Original report: #24

[melloware]

@0xeb is there a change the pictview plugin can be rewritten to not use that proprietary DLL? I love this plugin I use it practically every day for screenshots and for clipping images etc. I would love it if it was just part your build.