Reject COSE_Key decode into a mismatched wolfCrypt key object

[aidangarske]

Description

• wc_CoseKey_Decode() picked the wolfCrypt importer from the peer's CBOR, not from the key the caller attached.
• WOLFCOSE_KEY stores that key in an untagged union, so the key. != NULL guards could not tell an ed25519_key from an ed448_key or an ecc_key.
• A peer sending crv=Ed448 to an attached 112 byte ed25519_key ran the Ed448 importer and wrote past the object. kty=EC2 aimed the 4208 byte ecc_key importer at it. This runs before any signature check.
• Adds WOLFCOSE_KEY.attachedType, set by the wc_CoseKey_Set*() functions, and matches every importer on it instead of the union member.
• A decoded kty/crv that does not match the attached type now returns WOLFCOSE_E_COSE_KEY_TYPE before any import runs.
• Verified against the reporter's PoCs with ASan, all now rejected. Full suite, force-failure, cmdline 30/30, and the NO_EDDSA, NO_ED448, and LEAN configs pass.
• Reported by Omoikane Labs for ZD22200
• also fixes static analysis error we have been seeing with wolfssl

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