Усилить безопасность и надёжность выполнения операций

crates/crank-registry/src/migrations.rs

@@ -586,6 +586,22 @@ pub async fn apply_postgres(pool: &PgPool) -> Result<(), sqlx::Error> {
     query("alter table approval_requests drop column if exists confirmation_body")
         .execute(pool)
         .await?;
+    query("alter table approval_requests add column if not exists execution_started_at timestamptz null")
+        .execute(pool)
+        .await?;
+    query("alter table approval_requests add column if not exists execution_attempts integer not null default 0")
+        .execute(pool)
+        .await?;
+    query("alter table approval_requests add column if not exists request_fingerprint text null")
+        .execute(pool)
+        .await?;
+    query(
+        "create unique index if not exists approval_requests_pending_fingerprint_idx
+         on approval_requests(agent_id, operation_id, operation_version, request_fingerprint)
+         where status = 'pending' and request_fingerprint is not null",
+    )
+    .execute(pool)
+    .await?;
     query(
         "create index if not exists approval_requests_agent_status_idx
          on approval_requests(workspace_id, agent_id, status, expires_at)",