feat: 算力引擎 Go 后端核心（new-api）

- 统一 OpenAI 兼容 /v1 中继 + 渠道/额度/令牌/流水
- 各领域包：relay 模型网关、model 数据层、controller 管理 API

common/proxy_url.go

@@ -0,0 +1,77 @@
+package common
+
+import (
+	"fmt"
+	"net"
+	"net/url"
+	"strconv"
+	"strings"
+)
+
+// ParseProxyURLStrict validates and normalizes a proxy URL for persistence.
+func ParseProxyURLStrict(rawProxyURL string) (*url.URL, error) {
+	parsedURL, _, err := parseProxyURL(rawProxyURL, false)
+	return parsedURL, err
+}
+
+// ParseProxyURLRuntime validates and normalizes a proxy URL for runtime use.
+// The boolean result reports whether a legacy path, query, or fragment was removed.
+func ParseProxyURLRuntime(rawProxyURL string) (*url.URL, bool, error) {
+	return parseProxyURL(rawProxyURL, true)
+}
+
+func parseProxyURL(rawProxyURL string, allowLegacySuffix bool) (*url.URL, bool, error) {
+	trimmedProxyURL := strings.TrimSpace(rawProxyURL)
+	if trimmedProxyURL == "" {
+		return nil, false, nil
+	}
+
+	parsedURL, err := url.Parse(trimmedProxyURL)
+	if err != nil {
+		return nil, false, fmt.Errorf("invalid proxy URL")
+	}
+	parsedURL.Scheme = strings.ToLower(parsedURL.Scheme)
+	switch parsedURL.Scheme {
+	case "http", "https", "socks5", "socks5h":
+	default:
+		return nil, false, fmt.Errorf("proxy URL must use http, https, socks5, or socks5h")
+	}
+	if parsedURL.Hostname() == "" {
+		return nil, false, fmt.Errorf("proxy URL must include a host")
+	}
+	if portText := parsedURL.Port(); portText != "" {
+		port, err := strconv.Atoi(portText)
+		if err != nil || port < 1 || port > 65535 {
+			return nil, false, fmt.Errorf("proxy URL must include a valid port")
+		}
+	}
+
+	hasQuery := parsedURL.RawQuery != "" || parsedURL.ForceQuery
+	hasFragment := strings.Contains(trimmedProxyURL, "#")
+	escapedPath := parsedURL.EscapedPath()
+	hasNonRootPath := escapedPath != "" && escapedPath != "/"
+	legacySuffixStripped := hasQuery || hasFragment || hasNonRootPath
+	if !allowLegacySuffix {
+		switch {
+		case hasQuery:
+			return nil, false, fmt.Errorf("proxy URL must not include a query")
+		case hasFragment:
+			return nil, false, fmt.Errorf("proxy URL must not include a fragment")
+		case hasNonRootPath:
+			return nil, false, fmt.Errorf("proxy URL must not include a path")
+		}
+	}
+
+	parsedURL.Path = ""
+	parsedURL.RawPath = ""
+	parsedURL.RawQuery = ""
+	parsedURL.ForceQuery = false
+	parsedURL.Fragment = ""
+	parsedURL.RawFragment = ""
+
+	if (parsedURL.Scheme == "socks5" || parsedURL.Scheme == "socks5h") && parsedURL.Port() == "" {
+		parsedURL.Host = net.JoinHostPort(parsedURL.Hostname(), "1080")
+	}
+
+	return parsedURL, legacySuffixStripped, nil
+}