fix(security): redact delegated token in formatted output

CHANGELOG.md

@@ -4,6 +4,11 @@ All notable changes to the CreateOS Rust SDK are recorded here.
 
 ## Unreleased
 
+### Fixed
+
+- Redact plaintext sandbox access tokens from debug output to prevent
+  accidental disclosure in logs.
+
 ### Added
 
 - Sandbox access token creation, inspection, rotation, and disabling methods.

src/instance.rs

@@ -739,6 +739,7 @@ mod access_token_tests {
 
         let created = owner.create_access_token().await.unwrap();
         assert_eq!(created.token, "skp_sb_first");
+        assert!(!format!("{created:?}").contains(&created.token));
         assert!(created.enabled && created.rotated_at.is_none());
         assert_eq!(
             owner

src/models.rs

@@ -356,7 +356,7 @@ Sandbox {
 });
 
 /// Plaintext delegated token returned only when created or rotated.
-#[derive(Clone, Debug, Deserialize)]
+#[derive(Clone, Deserialize)]
 pub struct SandboxAccessTokenCreateResponse {
     /// Delegated credential. Store it securely; it cannot be read again.
     pub token: String,
@@ -368,6 +368,18 @@ pub struct SandboxAccessTokenCreateResponse {
     pub rotated_at: Option<DateTime<Utc>>,
 }
 
+impl fmt::Debug for SandboxAccessTokenCreateResponse {
+    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
+        formatter
+            .debug_struct("SandboxAccessTokenCreateResponse")
+            .field("token", &"[REDACTED]")
+            .field("enabled", &self.enabled)
+            .field("created_at", &self.created_at)
+            .field("rotated_at", &self.rotated_at)
+            .finish()
+    }
+}
+
 /// Delegated token state without plaintext credential material.
 #[derive(Clone, Debug, Deserialize)]
 pub struct SandboxAccessTokenMetadata {