feat: Compress PNG; detect and compare the size of compressed and uncompressed file

What does this PR do? (Please give us a brief description of what this PR does.)

• Allows compressing PNG images to jpeg

  Many screenshot tools, such as the default screenshot tool in Windows, generate png images and will not compress them when uploading before this commit.

• Detect and compare the size of compressed and uncompressed file, preventing uploaded "compressed" images from being larger than the source file

  This happens in webp -> png frequently

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