Allow defining const negative NonZero.

[orizi]

Stack:

• Added support for div-rem const folding. #6428
• Fixing const folded NonZero types. #6427
• Added additional tests for bounded_int const folding. #6426
• Allow defining const negative NonZero. #6425 ⬅
• Added NonZero() for const value fmt. #6424
• Using Zero and One instead of old traits. #6423

⚠️ Part of a stack created by spr. Do not merge manually using the UI - doing so may have unexpected results.

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[gilbens-starkware]

Reviewed 1 of 1 files at r1, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @orizi)