chore: update dependencies and CI actions

- Update Go dependencies to latest versions
- Bump Go version from 1.25.1 to 1.26
- Modernize code: interface{} -> any, strings.Split -> strings.SplitSeq
- Update GitHub Actions to latest versions:
  - actions/checkout: v3/v4 -> v6
  - actions/setup-go: v3 -> v6 (use go-version-file)
  - actions/upload-artifact: v4 -> v7
  - docker/setup-qemu-action: v3 -> v4
  - docker/setup-buildx-action: v3 -> v4
  - docker/login-action: v3 -> v4
  - docker/build-push-action: v6 -> v7
- Remove hardcoded GO_VERSION env var, read from go.mod

proxy/dial.go

@@ -72,7 +72,7 @@ func newProxyDial(proxyUrls string) proxy.Dialer {
 	var proxyDialer proxy.Dialer = proxy.Direct // 初始为直接连接，不使用代理
 
 	// 支持多个代理 URL（以逗号分隔）
-	for _, proxyUrl := range strings.Split(proxyUrls, ",") {
+	for proxyUrl := range strings.SplitSeq(proxyUrls, ",") {
 		proxyUrl = strings.TrimSpace(proxyUrl) // 去除首尾空格
 		if proxyUrl == "" {                    // 跳过空的代理 URL
 			continue