Manuscript Image Shadow Removal

I have a high-resolution photograph of a single manuscript page that needs to look clean and print-ready. The key task is to remove a hard shadow that runs across part of the sheet, then straighten the image so the margins sit perfectly square. No other alterations are required: the texture, colour and character of the original paper must stay intact—just an even lighting across the whole page and proper alignment.

The omauscript's contents must be clean and readable.

Please work non-destructively in Adobe Photoshop (or an equivalent tool) so I can review layers if needed. When finished, export a print-quality TIFF (300 dpi) plus a flattened JPEG for quick reference.