fix: harden official resource sync retries

infrastructure/src/official_download.rs

@@ -329,6 +329,21 @@ impl OfficialResourcePullService {
             return Err(format!("Refusing to fetch non-official URL: {url}"));
         }
 
+        let attempts = self.retry_attempts.max(1);
+        let mut last_error = None;
+        for attempt in 1..=attempts {
+            match self.fetch_bytes_once(url) {
+                Ok(bytes) => return Ok(bytes),
+                Err(error) => {
+                    last_error = Some(format!("attempt {attempt}/{attempts}: {error}"));
+                }
+            }
+        }
+
+        Err(last_error.unwrap_or_else(|| format!("curl failed for {url} without an attempt")))
+    }
+
+    fn fetch_bytes_once(&self, url: &str) -> Result<Vec<u8>, String> {
         let output = Command::new(&self.curl_command)
             .arg("--fail")
             .arg("--location")
@@ -1078,7 +1093,7 @@ mod tests {
     fn inventory() -> YostarJpDownloadInventory {
         YostarJpDownloadInventory::from_catalog_bytes(
             b"FullPatch_000.zip",
-            b"ExcelDB.db",
+            b"ExcelDB.db ExcelDB.db",
             b"JP_Airi.zip",
         )
     }
@@ -1680,6 +1695,31 @@ fi
         );
     }
 
+    #[test]
+    fn retries_transient_fetch_bytes_failures() {
+        let out_dir = TempDir::new().unwrap();
+        let bin_dir = TempDir::new().unwrap();
+        let curl_path = bin_dir.path().join("curl");
+        write_fake_flaky_curl(&curl_path);
+
+        let service = OfficialResourcePullService::with_curl_command(out_dir.path(), &curl_path)
+            .with_retry_attempts(2);
+        let bytes = service
+            .fetch_bytes(
+                "https://prod-clientpatch.bluearchiveyostar.com/r93_token/TableBundles/TableCatalog.bytes",
+            )
+            .unwrap();
+
+        assert_eq!(
+            String::from_utf8(bytes).unwrap(),
+            "https://prod-clientpatch.bluearchiveyostar.com/r93_token/TableBundles/TableCatalog.bytes"
+        );
+        assert_eq!(
+            fs::read_to_string(curl_path.with_extension("state")).unwrap(),
+            "2"
+        );
+    }
+
     #[test]
     fn rejects_non_official_urls() {
         let service = OfficialResourcePullService::new("/tmp/unused");