feat: impl iterator of moduleConfigs (#386)

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##### Checklist
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- [x] `npm test` passes
- [x] tests and/or benchmarks are included
- [ ] documentation is changed or added
- [ ] commit message follows commit guidelines

##### Affected core subsystem(s)
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##### Description of change
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Feat: support iterator of moduleConfigs
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- any feature?
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<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **New Features**
* Module configuration API now supports direct iteration over entries
for easier traversal and inspection.

* **Tests**
* Added tests verifying iteration behavior, entry order and content, and
empty-configuration scenarios.

<sub>✏️ Tip: You can customize this high-level summary in your review
settings.</sub>
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Author: RaoHai

core/common-util/src/ModuleConfigs.ts

@@ -7,4 +7,8 @@ export class ModuleConfigs {
   get(moduleName: string): ModuleConfig | undefined {
     return this.inner[moduleName]?.config;
   }
+
+  * [Symbol.iterator](): Iterator<[string, ModuleConfigHolder]> {
+    yield* Object.entries(this.inner);
+  }
 }

core/common-util/test/ModuleConfig.test.ts

@@ -1,6 +1,7 @@
 import { strict as assert } from 'node:assert';
 import path from 'node:path';
 import { ModuleConfigUtil } from '../src/ModuleConfig';
+import { ModuleConfigs } from '../src/ModuleConfigs';
 import type { ModuleReference } from '@eggjs/tegg-types';
 
 describe('test/ModuleConfig.test.ts', () => {
@@ -140,6 +141,45 @@ describe('test/ModuleConfig.test.ts', () => {
       }]);
     });
   });
+
+  it('should iterate over all module configs', () => {
+    const mockInner = {
+      module1: {
+        name: 'module1',
+        reference: { path: '/path/to/module1', name: 'module1' },
+        config: { foo: 'bar' },
+      },
+      module2: {
+        name: 'module2',
+        reference: { path: '/path/to/module2', name: 'module2' },
+        config: { baz: 'qux' },
+      },
+    };
+
+    const moduleConfigs = new ModuleConfigs(mockInner);
+    const result: Array<[string, any]> = [];
+
+    for (const [ name, holder ] of moduleConfigs) {
+      result.push([ name, holder ]);
+    }
+
+    assert.strictEqual(result.length, 2);
+    assert.strictEqual(result[0][0], 'module1');
+    assert.deepStrictEqual(result[0][1], mockInner.module1);
+    assert.strictEqual(result[1][0], 'module2');
+    assert.deepStrictEqual(result[1][1], mockInner.module2);
+  });
+
+  it('should work with empty configs', () => {
+    const moduleConfigs = new ModuleConfigs({});
+    const result: Array<[string, any]> = [];
+
+    for (const [ name, holder ] of moduleConfigs) {
+      result.push([ name, holder ]);
+    }
+
+    assert.strictEqual(result.length, 0);
+  });
 });
 
 describe('ModuleConfigUtil.deduplicateModules', () => {
@@ -323,3 +363,4 @@ describe('ModuleConfigUtil.deduplicateModules', () => {
     });
   });
 });
+