fix(quota): reject oversized multipart completion (#5958)

* fix(quota): reject oversized multipart completion

* fix(arch): route quota test through app facade

crates/ecstore/src/data_usage/mod.rs

@@ -1638,7 +1638,7 @@ fn preserve_unknown_dirty_usage(
     Some(preserved)
 }
 
-#[cfg(test)]
+#[cfg(any(test, feature = "test-util"))]
 async fn replace_bucket_usage_memory_from_authoritative(bucket: &str, usage: BucketUsageInfo, refresh_started_at: SystemTime) {
     let mut cache = memory_cache().write().await;
     if let Some(existing) = cache.get(bucket)
@@ -1650,6 +1650,19 @@ async fn replace_bucket_usage_memory_from_authoritative(bucket: &str, usage: Buc
     cache.insert(bucket.to_string(), cached_bucket_usage_from_backend(usage, refresh_started_at, true));
 }
 
+#[cfg(feature = "test-util")]
+pub async fn seed_bucket_usage_memory_for_test(bucket: &str, size: u64) {
+    replace_bucket_usage_memory_from_authoritative(
+        bucket,
+        BucketUsageInfo {
+            size,
+            ..Default::default()
+        },
+        SystemTime::now(),
+    )
+    .await;
+}
+
 /// Fast in-memory update for immediate quota and admin usage consistency.
 pub async fn record_bucket_object_write_memory(bucket: &str, previous_current_size: Option<u64>, new_size: u64) {
     record_bucket_object_write_memory_inner(bucket, previous_current_size, new_size, false).await;