fix: 优化CI覆盖率生成流程

- 添加覆盖率清理步骤，避免冲突
- 改进错误检测和日志输出
- 移除可能导致问题的moon run步骤
- 添加verbose模式便于调试

Author: conisng

.github/workflows/ci.yml

@@ -22,22 +22,22 @@ jobs:
       run: |
         moon check
         moon test
-        moon run src/test.mbt
     
     - name: Generate Coverage Report
       run: |
+        # 清理之前的覆盖率文件
+        moon coverage clean
         # 运行MoonBit测试并生成覆盖率
         moon coverage analyze
         # 生成Codecov兼容的coverage报告
         moon coverage report -f coveralls -o coverage.json
-        # 显示生成的文件
-        ls -la coverage.*
-        echo "Generated coverage files:"
+        # 验证文件生成
         if [ -f "coverage.json" ]; then
-          echo "✅ coverage.json generated successfully"
-          head -20 coverage.json
+          echo "✅ Coverage report generated successfully"
+          echo "File size: $(wc -c < coverage.json) bytes"
         else
           echo "❌ coverage.json not found"
+          exit 1
         fi
     
     - name: Upload Coverage to Codecov
@@ -47,4 +47,5 @@ jobs:
         file: ./coverage.json
         flags: unittests
         name: codecov-umbrella
-        fail_ci_if_error: false
+        fail_ci_if_error: false
+        verbose: true