fixed all tests

libs/core/config/src/config-manager.ts

@@ -199,31 +199,44 @@ export class ConfigManager<T = Record<string, unknown>> {
   }
 
   /**
-   * Simple deep merge without circular reference handling
+   * Deep merge with circular reference handling
    */
   private merge(...objects: Record<string, unknown>[]): Record<string, unknown> {
-    const result: Record<string, unknown> = {};
+    const seen = new WeakSet();
+    
+    const mergeRecursive = (...objs: Record<string, unknown>[]): Record<string, unknown> => {
+      const result: Record<string, unknown> = {};
 
-    for (const obj of objects) {
-      for (const [key, value] of Object.entries(obj)) {
-        if (value === null || value === undefined) {
-          result[key] = value;
-        } else if (
-          typeof value === 'object' &&
-          !Array.isArray(value) &&
-          !(value instanceof Date) &&
-          !(value instanceof RegExp)
-        ) {
-          result[key] = this.merge(
-            (result[key] as Record<string, unknown>) || {},
-            value as Record<string, unknown>
-          );
-        } else {
-          result[key] = value;
+      for (const obj of objs) {
+        for (const [key, value] of Object.entries(obj)) {
+          if (value === null || value === undefined) {
+            result[key] = value;
+          } else if (
+            typeof value === 'object' &&
+            !Array.isArray(value) &&
+            !(value instanceof Date) &&
+            !(value instanceof RegExp)
+          ) {
+            // Check for circular reference
+            if (seen.has(value)) {
+              result[key] = '[Circular]';
+              continue;
+            }
+            seen.add(value);
+            
+            result[key] = mergeRecursive(
+              (result[key] as Record<string, unknown>) || {},
+              value as Record<string, unknown>
+            );
+          } else {
+            result[key] = value;
+          }
         }
       }
-    }
 
-    return result;
+      return result;
+    };
+    
+    return mergeRecursive(...objects);
   }
 }

libs/core/config/src/index.ts

@@ -24,3 +24,26 @@ export function createAppConfig<T>(
 ): ConfigManager<T> {
   return new ConfigManager<T>(options);
 }
+
+// Export utilities
+export {
+  SecretValue,
+  secret,
+  isSecret,
+  isSecretEnvVar,
+  COMMON_SECRET_PATTERNS,
+  redactSecrets,
+  wrapSecretEnvVars,
+  secretSchema,
+  secretStringSchema
+} from './utils/secrets';
+
+export {
+  checkRequiredEnvVars,
+  createStrictSchema,
+  formatValidationResult,
+  mergeSchemas,
+  validateConfig,
+  validateCompleteness,
+  type ValidationResult
+} from './utils/validation';