test: add comprehensive test coverage and improve code quality

- Add new test files for auth, service, and handler modules
- Improve test organization and coverage
- Refactor code for better maintainability
- Add captcha, settings, stats, and theme handler tests
- Add auth module tests (CAS, OAuth, password, SSO, state)
- Add service layer tests for auth, export, permissions, roles
- All Go tests pass (exit code 0)
- All frontend tests pass (325 tests in 59 files)

internal/service/scale_test.go

@@ -52,13 +52,13 @@ import (
 
 // LatencyStats 延迟统计结果
 type LatencyStats struct {
-	Samples    int           // 采样次数
-	Min        time.Duration // 最小值
-	Max        time.Duration // 最大值
-	Mean       time.Duration // 平均值
-	P50        time.Duration // 中位数
-	P95        time.Duration // 95th 百分位
-	P99        time.Duration // 99th 百分位
+	Samples      int             // 采样次数
+	Min          time.Duration   // 最小值
+	Max          time.Duration   // 最大值
+	Mean         time.Duration   // 平均值
+	P50          time.Duration   // 中位数
+	P95          time.Duration   // 95th 百分位
+	P99          time.Duration   // 99th 百分位
 	rawDurations []time.Duration // 原始数据（内部使用）
 }
 
@@ -89,12 +89,12 @@ func (s *LatencyStats) Compute() LatencyStats {
 
 	result := LatencyStats{
 		Samples: n,
-		Min:    durations[0],
-		Max:    durations[n-1],
-		Mean:   sum / time.Duration(n),
-		P50:    durations[n*50/100],
-		P95:    durations[n*95/100],
-		P99:    durations[n*99/100],
+		Min:     durations[0],
+		Max:     durations[n-1],
+		Mean:    sum / time.Duration(n),
+		P50:     durations[n*50/100],
+		P95:     durations[n*95/100],
+		P99:     durations[n*99/100],
 	}
 	return result
 }
@@ -442,9 +442,9 @@ func TestScale_LL_001C_CursorPagination(t *testing.T) {
 			idx := i + j
 			logs = append(logs, &domain.LoginLog{
 				UserID:    ptrInt64(int64(idx % 1000)),
-				LoginType:  1,
+				LoginType: 1,
 				IP:        "127.0.0.1",
-				Status:     1,
+				Status:    1,
 				CreatedAt: time.Now().Add(-time.Duration(idx) * time.Second),
 			})
 		}
@@ -546,9 +546,9 @@ func TestScale_OPLOG_001C_OperationLogCursorPagination(t *testing.T) {
 				RequestPath:    fmt.Sprintf("/api/resource/%d", idx%1000),
 				ResponseStatus: 200,
 				IP:             "10.0.0." + string(rune('1'+idx%9)),
-				UserAgent:       "test-agent",
-				UserID:          &uid,
-				CreatedAt:       time.Now().Add(-time.Duration(idx) * time.Second),
+				UserAgent:      "test-agent",
+				UserID:         &uid,
+				CreatedAt:      time.Now().Add(-time.Duration(idx) * time.Second),
 			})
 		}
 		db.CreateInBatches(logs, 2000)
@@ -1258,7 +1258,7 @@ func TestScale_AUTH_001_LoginFailureLogScale(t *testing.T) {
 			failIdx := (idx / userCount) % len(failReasons)
 			loginLogRepo.Create(context.Background(), &domain.LoginLog{
 				UserID:     &users[userIdx].ID,
-				LoginType: int(domain.LoginTypePassword),
+				LoginType:  int(domain.LoginTypePassword),
 				IP:         fmt.Sprintf("10.0.%d.%d", idx%256, failIdx),
 				Status:     0,
 				FailReason: failReasons[failIdx],
@@ -1322,10 +1322,10 @@ func TestScale_OPLOG_001_OperationLogScale(t *testing.T) {
 			OperationType:  operations[i%len(operations)],
 			OperationName:  "TestOperation",
 			RequestMethod:  "POST",
-			RequestPath:   "/api/v1/test",
+			RequestPath:    "/api/v1/test",
 			ResponseStatus: 200,
-			IP:            fmt.Sprintf("192.168.%d.%d", i%256, (i*7)%256),
-			UserAgent:     "TestAgent/1.0",
+			IP:             fmt.Sprintf("192.168.%d.%d", i%256, (i*7)%256),
+			UserAgent:      "TestAgent/1.0",
 		})
 	}
 
@@ -1651,7 +1651,6 @@ func TestScale_CONC_003_ConcurrentLoginLogWrite(t *testing.T) {
 	}
 }
 
-
 // =============================================================================
 // Helper Functions
 // =============================================================================