build(go): 更新 ip2region 依赖版本并调整数据库文件路径

更新 github.com/lionsoul2014/ip2region/binding/golang 依赖至最新版本，
同时将 IP 数据库文件路径从 ip2region.xdb 调整为 ip2region_v4.xdb。

go.mod

@@ -4,7 +4,7 @@ go 1.25.4
 
 require (
 	github.com/google/gopacket v1.1.19
-	github.com/lionsoul2014/ip2region/binding/golang v0.0.0-20251113013923-bd30b77d5468
+	github.com/lionsoul2014/ip2region/binding/golang v0.0.0-20251121144738-613501fc0093
 )
 
 require (

go.sum

@@ -6,6 +6,8 @@ github.com/lionsoul2014/ip2region/binding/golang v0.0.0-20251015133354-5a51b7541
 github.com/lionsoul2014/ip2region/binding/golang v0.0.0-20251015133354-5a51b754117e/go.mod h1:+mNMTBuDMdEGhWzoQgc6kBdqeaQpWh5ba8zqmp2MxCU=
 github.com/lionsoul2014/ip2region/binding/golang v0.0.0-20251113013923-bd30b77d5468 h1:tAxRAx434lf9txMOrgrMVPIAm2/7nB7SkL5v7NnO8Cc=
 github.com/lionsoul2014/ip2region/binding/golang v0.0.0-20251113013923-bd30b77d5468/go.mod h1:+mNMTBuDMdEGhWzoQgc6kBdqeaQpWh5ba8zqmp2MxCU=
+github.com/lionsoul2014/ip2region/binding/golang v0.0.0-20251121144738-613501fc0093 h1:+vHmV2SqaCMxb21SuOvezhBFKlUdaB8pYfDIDOhU64Y=
+github.com/lionsoul2014/ip2region/binding/golang v0.0.0-20251121144738-613501fc0093/go.mod h1:+mNMTBuDMdEGhWzoQgc6kBdqeaQpWh5ba8zqmp2MxCU=
 github.com/mitchellh/go-homedir v1.1.0 h1:lukF9ziXFxDFPkA1vsr5zpc1XuPDn/wFntq5mG+4E0Y=
 github.com/mitchellh/go-homedir v1.1.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=

ip2region.go

@@ -8,7 +8,7 @@ import (
 
 func ip2region(ip string) (string, error) {
 	version := xdb.IPv4
-	var dbPath = "ip2region/ip2region.xdb"
+	var dbPath = "ip2region/ip2region_v4.xdb"
 
 	searcher, err := xdb.NewWithFileOnly(version, dbPath)
 	if err != nil {