fix: add missing export statements in unit test files

Author: winterdrive

src/test/unit/addGroupScope.test.ts

@@ -91,3 +91,5 @@ describe('addGroup scope 自動決定邏輯', () => {
         });
     });
 });
+
+export {};

src/test/unit/groupAggregation.test.ts

@@ -119,3 +119,5 @@ describe('群組聚合邏輯單元測試', () => {
         expect(aggregated[0].files).toEqual(['file1.ts', 'file2.ts']);
     });
 });
+
+export {};

src/test/unit/scopeDescription.test.ts

@@ -135,3 +135,5 @@ describe('computeScopeDescription', () => {
         });
     });
 });
+
+export {};

src/test/unit/scopeFilterRoot.test.ts

@@ -225,3 +225,5 @@ describe('scope 篩選後根層 tree 結構', () => {
         });
     });
 });
+
+export {};