testing/staging fixin

src/config/env.ts

@@ -128,7 +128,7 @@ const workerSchema = z.object({
  * Server configuration schema.
  */
 const serverSchema = z.object({
-  nodeEnv: z.enum(['development', 'production', 'test']).default('development'),
+  nodeEnv: z.enum(['development', 'production', 'test', 'staging']).default('development'),
   port: intWithDefault(3001),
   frontendUrl: z.string().url().optional(),
   baseUrl: z.string().optional(),
@@ -318,6 +318,11 @@ export const isTest = config.server.nodeEnv === 'test';
  */
 export const isDevelopment = config.server.nodeEnv === 'development';
 
+/**
+ * Returns true if running in staging environment.
+ */
+export const isStaging = config.server.nodeEnv === 'staging';
+
 /**
  * Returns true if SMTP is configured (all required fields present).
  */