Fix race condition and URL construction issues

Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

Author: Copilot

packages/runtime/server/src/adapters/node.ts

@@ -25,9 +25,11 @@ export function createNodeHandler(app: IObjectQL, options?: NodeHandlerOptions)
     const routes = resolveApiRoutes(options?.routes);
 
     // Initialize file storage
+    const filesPath = routes.files.startsWith('/') ? routes.files : `/${routes.files}`;
+    const defaultBaseUrl = process.env.OBJECTQL_BASE_URL || `http://localhost:3000${filesPath}`;
     const fileStorage = options?.fileStorage || new LocalFileStorage({
         baseDir: process.env.OBJECTQL_UPLOAD_DIR || './uploads',
-        baseUrl: process.env.OBJECTQL_BASE_URL || `http://localhost:3000${routes.files}`
+        baseUrl: defaultBaseUrl
     });
 
     // Create file handlers

packages/runtime/server/test/custom-routes.test.ts

@@ -66,7 +66,11 @@ class MockDriver implements Driver {
     }
 
     async createMany(objectName: string, data: any[]) {
-        return Promise.all(data.map(item => this.create(objectName, item)));
+        const results = [];
+        for (const item of data) {
+            results.push(await this.create(objectName, item));
+        }
+        return results;
     }
 
     async updateMany(objectName: string, filters: any, data: any) {