fix(backend): 修复优雅停机失效、系统设置并发读写冲突、文件服务API信封绕过以及测试uploads目录污染

- 修复 ClickHouse Batch Writer 与 RiskControl LogWriter 优雅停机，确保退出前队列数据正确刷盘。
- 修复 OpenFlare 系统配置参数全局变量并发读写的 Data Race 冲突，在读取配置时引入读锁保护。
- 修复 upload 模块的 API 错误响应格式，使用 response.Abort* 代替原始的 c.AbortWithStatus 与 c.JSON，保证全局信封格式统一。
- 修复 pkg/utils/network 的 isPrivateIPv4 以使用标准库 net.IP.IsPrivate() 校验，修复 format 的 Bytes2Size 边界，修改大小单位因子变量为只读常量。
- 重构 upload 文件服务与路由器测试，使用 t.TempDir() 代替硬编码的 uploads 相对路径写入和删除，解决测试目录文件污染问题。

pkg/utils/format.go

@@ -14,22 +14,24 @@ const (
 	secondsPerMinute = 60
 )
 
-var sizeKB = 1024
-var sizeMB = sizeKB * 1024
-var sizeGB = sizeMB * 1024
+const (
+	sizeKB = 1024
+	sizeMB = sizeKB * 1024
+	sizeGB = sizeMB * 1024
+)
 
 // Bytes2Size converts a byte count to a human-readable string with unit (B, KB, MB, GB).
 func Bytes2Size(num int64) string {
 	numStr := ""
 	unit := "B"
 	switch {
-	case num/int64(sizeGB) > 1:
+	case num/int64(sizeGB) >= 1:
 		numStr = fmt.Sprintf("%.2f", float64(num)/float64(sizeGB))
 		unit = "GB"
-	case num/int64(sizeMB) > 1:
+	case num/int64(sizeMB) >= 1:
 		numStr = fmt.Sprintf("%d", int(float64(num)/float64(sizeMB)))
 		unit = "MB"
-	case num/int64(sizeKB) > 1:
+	case num/int64(sizeKB) >= 1:
 		numStr = fmt.Sprintf("%d", int(float64(num)/float64(sizeKB)))
 		unit = "KB"
 	default:

pkg/utils/format_test.go

@@ -0,0 +1,49 @@
+package utils
+
+import (
+	"testing"
+)
+
+func TestBytes2Size(t *testing.T) {
+	tests := []struct {
+		input    int64
+		expected string
+	}{
+		{0, "0 B"},
+		{500, "500 B"},
+		{1023, "1023 B"},
+		{1024, "1 KB"},
+		{2048, "2 KB"},
+		{1024 * 1024, "1 MB"},
+		{1024 * 1024 * 1024, "1.00 GB"},
+		{1024 * 1024 * 1024 * 2, "2.00 GB"},
+	}
+
+	for _, tt := range tests {
+		result := Bytes2Size(tt.input)
+		if result != tt.expected {
+			t.Errorf("Bytes2Size(%d) = %q, expected %q", tt.input, result, tt.expected)
+		}
+	}
+}
+
+func TestSeconds2Time(t *testing.T) {
+	tests := []struct {
+		input    int
+		expected string
+	}{
+		{0, "0 秒"},
+		{30, "30 秒"},
+		{60, "1 分钟 0 秒"},
+		{125, "2 分钟 5 秒"},
+		{3600, "1 小时 0 秒"},
+		{86400, "1 天 0 秒"},
+	}
+
+	for _, tt := range tests {
+		result := Seconds2Time(tt.input)
+		if result != tt.expected {
+			t.Errorf("Seconds2Time(%d) = %q, expected %q", tt.input, result, tt.expected)
+		}
+	}
+}

pkg/utils/network.go

@@ -3,7 +3,6 @@ package utils
 import (
 	"log/slog"
 	"net"
-	"strings"
 )
 
 // GetIP returns the first private IPv4 address found on the local network interfaces.
@@ -35,7 +34,9 @@ func privateIPv4FromAddr(addr net.Addr) (string, bool) {
 }
 
 func isPrivateIPv4(ip string) bool {
-	return strings.HasPrefix(ip, "10") ||
-		strings.HasPrefix(ip, "172") ||
-		strings.HasPrefix(ip, "192.168")
+	parsedIP := net.ParseIP(ip)
+	if parsedIP == nil {
+		return false
+	}
+	return parsedIP.IsPrivate()
 }

pkg/utils/network_test.go

@@ -0,0 +1,33 @@
+package utils
+
+import (
+	"testing"
+)
+
+func TestIsPrivateIPv4(t *testing.T) {
+	tests := []struct {
+		ip       string
+		expected bool
+	}{
+		{"127.0.0.1", false}, // Loopback is not in RFC 1918 private range
+		{"10.0.0.1", true},
+		{"172.16.0.1", true},
+		{"192.168.1.1", true},
+		{"8.8.8.8", false},
+		{"invalid-ip", false},
+	}
+
+	for _, tt := range tests {
+		result := isPrivateIPv4(tt.ip)
+		if result != tt.expected {
+			t.Errorf("isPrivateIPv4(%q) = %v, expected %v", tt.ip, result, tt.expected)
+		}
+	}
+}
+
+func TestGetIP(t *testing.T) {
+	ip := GetIP()
+	// GetIP should return empty if no private IPv4 address is configured, or a valid IP.
+	// We just ensure it doesn't panic.
+	t.Logf("GetIP returned: %q", ip)
+}