feat(sync): full code sync from release

backend/internal/handler/ops_error_logger_test.go

@@ -6,6 +6,7 @@ import (
 	"sync"
 	"testing"
 
+	middleware2 "github.com/Wei-Shaw/sub2api/internal/server/middleware"
 	"github.com/Wei-Shaw/sub2api/internal/service"
 	"github.com/gin-gonic/gin"
 	"github.com/stretchr/testify/require"
@@ -173,3 +174,43 @@ func TestEnqueueOpsErrorLog_EarlyReturnBranches(t *testing.T) {
 	enqueueOpsErrorLog(ops, entry)
 	require.Equal(t, int64(0), OpsErrorLogEnqueuedTotal())
 }
+
+func TestOpsCaptureWriterPool_ResetOnRelease(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+
+	rec := httptest.NewRecorder()
+	c, _ := gin.CreateTestContext(rec)
+	c.Request = httptest.NewRequest(http.MethodGet, "/test", nil)
+
+	writer := acquireOpsCaptureWriter(c.Writer)
+	require.NotNil(t, writer)
+	_, err := writer.buf.WriteString("temp-error-body")
+	require.NoError(t, err)
+
+	releaseOpsCaptureWriter(writer)
+
+	reused := acquireOpsCaptureWriter(c.Writer)
+	defer releaseOpsCaptureWriter(reused)
+
+	require.Zero(t, reused.buf.Len(), "writer should be reset before reuse")
+}
+
+func TestOpsErrorLoggerMiddleware_DoesNotBreakOuterMiddlewares(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+
+	r := gin.New()
+	r.Use(middleware2.Recovery())
+	r.Use(middleware2.RequestLogger())
+	r.Use(middleware2.Logger())
+	r.GET("/v1/messages", OpsErrorLoggerMiddleware(nil), func(c *gin.Context) {
+		c.Status(http.StatusNoContent)
+	})
+
+	rec := httptest.NewRecorder()
+	req := httptest.NewRequest(http.MethodGet, "/v1/messages", nil)
+
+	require.NotPanics(t, func() {
+		r.ServeHTTP(rec, req)
+	})
+	require.Equal(t, http.StatusNoContent, rec.Code)
+}