refactor: 删除 deadcode 检测出的未使用函数

- proxy/detector.go: 删除 IsSOCKS5Standard, IsProxyInitialized
- findnet.go: 删除 NetworkInfo.OneLine, TreeFormat 方法
- port_scan.go: 删除 estimateScanTime 函数
- web_scanner.go: 删除 GetFingerprints 函数
- 清理相关测试代码

core/web_scanner.go

@@ -300,17 +300,6 @@ func SetFingerprints(host string, port int, fingerprints []string) {
 	fingerprintCache[cacheKey] = fingerprints
 }
 
-// GetFingerprints 获取目标的指纹信息
-func GetFingerprints(host string, port int) ([]string, bool) {
-	cacheKey := fmt.Sprintf("%s:%d", host, port)
-
-	fingerprintCacheMutex.RLock()
-	defer fingerprintCacheMutex.RUnlock()
-
-	fingerprints, exists := fingerprintCache[cacheKey]
-	return fingerprints, exists
-}
-
 // ===============================
 // Web扫描策略
 // ===============================