fix: serialize Stripe checkout provisioning

src/services/idempotency.rs

@@ -3,7 +3,6 @@ use crate::state::AppState;
 
 use chrono::{DateTime, Duration, Utc};
 use serde_json::Value as JsonValue;
-use sha2::{Digest, Sha256};
 use sqlx::FromRow;
 use uuid::Uuid;
 
@@ -27,15 +26,6 @@ struct IdemRow {
     response_body: Option<JsonValue>,
 }
 
-pub fn sha256_hex(parts: &[&[u8]]) -> String {
-    let mut hasher = Sha256::new();
-    for p in parts {
-        hasher.update(p);
-        hasher.update([0u8]); // separator
-    }
-    hex::encode(hasher.finalize())
-}
-
 pub async fn begin(
     state: &AppState,
     scope: Scope,