feat(u32): add checked constant XOR adapter - #132

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struct `HybridPayloadCost` is never constructed

struct `TableCost` is never constructed

variant `DirectKLimbs` is never constructed

variant `Addition` is never constructed

unused import: `hashes::Hash`

function `qfree_entry_items_for_widths` is never used

variant `OptimizedMixed` is never constructed

use of deprecated associated function `signatures::winternitz::legacy::api::Wots::secret_from_str`: It is safer to use Vec<u8> directly

unused import: `Signed`

unused import: `BigInt`