createOperation was building effectiveParams from key-generation params but dropping operation-time fields (nonce, blockMode, padding, minMacLength). This caused GCM decrypt to fail with "IV must be specified in GCM mode" since the nonce from the begin call never reached CipherPrimitive. Also adds nonce field to KeyMintAttestation and handles GCM/CBC/CTR IV initialization in CipherPrimitive.