chore(deps): migrate direct encoding deps to simd (#6690)

crates/kms/tests/behavior_lifecycle.rs

@@ -451,6 +451,5 @@ async fn harness_restart_brings_the_service_back_over_the_same_state() {
 }
 
 fn base64_of(bytes: &[u8]) -> String {
-    use base64::Engine as _;
-    base64::engine::general_purpose::STANDARD.encode(bytes)
+    base64_simd::STANDARD.encode_to_string(bytes)
 }

crates/kms/tests/behavior_objects.rs

@@ -667,7 +667,7 @@ async fn sse_c_round_trips_and_rejects_the_wrong_key() {
 async fn sse_c_validates_the_supplied_key_md5() {
     let (_kms, service) = service_with_key("sse-c-md5-unused").await;
     let customer_key = [0x33u8; 32];
-    let correct_md5 = hex::encode(md5_of(&customer_key));
+    let correct_md5 = hex_simd::encode_to_string(md5_of(&customer_key), hex_simd::AsciiCase::Lower);
 
     service
         .encrypt_object_with_customer_key(BUCKET, "md5-ok.bin", payload(64).as_slice(), &customer_key, Some(&correct_md5))

crates/kms/tests/common/mod.rs

@@ -34,8 +34,7 @@ use std::future::Future;
 use std::path::PathBuf;
 use std::sync::{Arc, Mutex};
 
-use base64::Engine as _;
-use base64::engine::general_purpose::STANDARD as BASE64;
+use base64_simd::STANDARD as BASE64;
 use rustfs_kms::backends::BackendCapabilities;
 use rustfs_kms::{
     CreateKeyRequest, DeleteKeyRequest, KeyUsage, KmsConfig, KmsError, KmsManager, KmsServiceManager, KmsServiceStatus,
@@ -51,7 +50,7 @@ pub const STATIC_KEY_ID: &str = "behavior-static-key";
 /// Fixed rather than random so a failure is reproducible; it is test-only
 /// material and never leaves this crate's test binaries.
 pub fn static_secret_key() -> String {
-    BASE64.encode([0x5au8; 32])
+    BASE64.encode_to_string([0x5au8; 32])
 }
 
 /// Which backend a harness instance is running.