fix(server): upload filters answer multer once on a throwing callback; positive call-graph gate test

server/scripts/__fixtures__/sync-db-sample.ts

@@ -0,0 +1,23 @@
+/**
+ * Fixture for `db-call-graph.mjs --sync --tx --root scripts/__fixtures__`: one class that
+ * still touches the database synchronously and opens a raw transaction, so the two gates
+ * CI runs (`--sync`, `--tx`) each have a known-bad case to report. `unawaited-sample.ts`
+ * beside it is clean under both flags.
+ */
+
+interface RawDb {
+  get(sql: string, ...args: unknown[]): unknown;
+  transaction<T>(fn: () => T): T;
+}
+
+export class SyncSample {
+  private db: RawDb = { get: () => undefined, transaction: (fn) => fn() };
+
+  readSync(id: number): unknown {
+    return this.db.get('SELECT 1 WHERE id = ?', id); // sync DB-touching method
+  }
+
+  writeInTx(): void {
+    this.db.transaction(() => undefined); // raw transaction site
+  }
+}