core: type platform api key timestamps

crates/crank-registry/src/postgres/mod.rs

@@ -1676,7 +1676,7 @@ mod tests {
             prefix: "crk_live".to_owned(),
             scopes: vec![PlatformApiKeyScope::Read, PlatformApiKeyScope::Write],
             status: PlatformApiKeyStatus::Active,
-            created_at: "2026-03-25T12:01:00Z".to_owned(),
+            created_at: timestamp("2026-03-25T12:01:00Z"),
             last_used_at: None,
         };
         let secret_hash = "secret_hash_01";
@@ -1717,7 +1717,7 @@ mod tests {
             .touch_platform_api_key(
                 &workspace.id,
                 &PlatformApiKeyId::new("key_01"),
-                "2026-03-25T12:05:00Z",
+                &timestamp("2026-03-25T12:05:00Z"),
             )
             .await
             .unwrap();
@@ -1727,8 +1727,8 @@ mod tests {
             .await
             .unwrap();
         assert_eq!(
-            touched[0].api_key.last_used_at.as_deref(),
-            Some("2026-03-25T12:05:00Z")
+            touched[0].api_key.last_used_at,
+            Some(timestamp("2026-03-25T12:05:00Z"))
         );
 
         database.cleanup().await;