[fakedev9999]

What

Pin the CLI toolchain to succinct-1.96.0-64bit-v3.
This selects the atomic-lowering fix from succinctlabs/rust#10 for toolchain installation and source builds.

Validation

• CLI build and five tests passed with --locked --no-default-features.
• CLI formatting and Clippy passed with warnings denied.
• The modified CLI downloaded and installed the published Apple ARM64 archive in an isolated HOME and RUSTUP_HOME.
• The installed archive SHA256 matches the published asset digest.
• The published toolchain passed off/thin/fat guest builds and normal/panic execution on all four hosts in release CI.
• Full workspace checks and Linux installer validation are deferred to PR CI.

[github-actions]

Test	Old	New	Diff
curve25519_dalek_test_decompressed_expected_value	4632800	4392389	-5.1893 %
bls12_381_tests_test_sqrt_fp_100	871385	808399	-7.2283 %
p256_test_recover_pubkey_infinity	96713	96713	0.0000 %
bls12_381_tests_test_bls_double_100	6290432	6290432	0.0000 %
secp256k1_program_test_recover_v0_30_0_rand_lte_100	5482098	5469367	-0.2322 %
sha_test_sha2_v0_9_9_expected_digest_lte_100_times	1254072	1257964	0.3103 %
curve25519_dalek_test_add_then_multiply	3417329	2878605	-15.7645 %
sha_test_sha2_v0_10_6_expected_digest_lte_100_times	1346824	1348535	0.1270 %
curve25519_dalek_test_zero_mul	71796	71796	0.0000 %
curve25519_dalek_test_decompressed_noncanonical	7766	7766	0.0000 %
k256_test_recover_rand_lte_100	4395019	4398861	0.0874 %
sha_test_sha2_v0_10_8_expected_digest_lte_100_times	1345565	1344921	-0.0479 %
curve25519_dalek_ng_test_zero_msm	125140	125140	0.0000 %
p256_test_verify_rand_lte_100	12055345	12072506	0.1424 %
secp256k1_program_test_verify_rand_lte_100	17069794	17096869	0.1586 %
secp256k1_program_test_verify_v0_30_0_rand_lte_100	17101302	17091574	-0.0569 %
rustcrypto_bigint_test_bigint_mul_add_residue	2063494	2063494	0.0000 %
keccack_test_expected_digest_lte_100	1713841	1712374	-0.0856 %
bn_test_bn_test_fq_partial_ord	185842	185842	0.0000 %
curve25519_dalek_ng_test_zero_mul	107744	107744	0.0000 %
k256_test_recover_pubkey_infinity	97499	97499	0.0000 %
k256_test_schnorr_verify	5730069	5726221	-0.0672 %
sha_test_sha3_expected_digest_lte_100_times	1180173	1180273	0.0085 %
bn_test_bn_test_g1_mul_zero	48309	48309	0.0000 %
p256_test_recover_high_hash_high_recid	5705344	5562494	-2.5038 %
p256_test_recover_rand_lte_100	15884510	15910812	0.1656 %
rust_crypto_rsa_test_pkcs_verify_100	29333023	29180516	-0.5199 %
k256_test_point_ops_edge_cases	33322	33322	0.0000 %
curve25519_dalek_test_zero_msm	83398	83398	0.0000 %
bls12_381_tests_test_bls_add_100	10365030	10365030	0.0000 %
bls12_381_tests_test_sqrt_fp2_100	1725842	1829747	6.0205 %
bn_test_bn_test_g1_msm_edge	373720	373720	0.0000 %
bls12_381_tests_test_inverse_fp2_100	2219563	2219563	0.0000 %
bn_test_bn_test_fr_inverse_100	818032	818032	0.0000 %
rustcrypto_bigint_test_bigint_mul_mod_special	1761306	1761306	0.0000 %
bn_test_bn_test_fq_inverse_100	801032	801032	0.0000 %
curve25519_dalek_test_ed25519_verify	12922646	12925779	0.0242 %
secp256k1_program_test_recover_rand_lte_100	5490341	5479823	-0.1916 %
bn_test_bn_test_g1_add_neg	297037	297037	0.0000 %
curve25519_dalek_ng_test_add_then_multiply	3917815	4811083	22.8002 %
k256_test_verify_rand_lte_100	11752518	11751482	-0.0088 %
curve25519_dalek_ng_test_decompressed_noncanonical	188498	188498	0.0000 %
sha_test_sha2_v0_10_9_expected_digest_lte_100_times	1347957	1344920	-0.2253 %
k256_test_recover_high_hash_high_recid	2306749	1877322	-18.6161 %
bn_test_bn_test_fq_sqrt_100	799432	799432	0.0000 %
sha_test_sha2_v0_11_0_expected_digest_lte_100_times	1339266	1336818	-0.1828 %
bls12_381_tests_test_inverse_fp_100	1199684	1199684	0.0000 %
bn_test_bn_test_g1_add_100	996432	996432	0.0000 %
bn_test_bn_test_g1_double_100	733939	733918	-0.0029 %