test: 补充单元测试覆盖率 29.9% → 36.6%

新建 18 个测试文件，追加 30 个已有测试文件，覆盖协议解析、
错误分类、CEL 表达式求值、YAML 反序列化、字节编码等纯函数。

webscan/lib/client_test.go

@@ -1,6 +1,114 @@
 package lib
 
-import "testing"
+import (
+	"testing"
+
+	"gopkg.in/yaml.v2"
+)
+
+// =============================================================================
+// UnmarshalYAML 测试
+// =============================================================================
+
+func TestStrMapUnmarshalYAML(t *testing.T) {
+	t.Run("正常键值对", func(t *testing.T) {
+		data := []byte("key1: val1\nkey2: val2\n")
+		var m StrMap
+		if err := yaml.Unmarshal(data, &m); err != nil {
+			t.Fatalf("yaml.Unmarshal error = %v", err)
+		}
+		if len(m) != 2 {
+			t.Fatalf("len = %d, want 2", len(m))
+		}
+		if m[0].Key != "key1" || m[0].Value != "val1" {
+			t.Errorf("m[0] = %+v, want {key1 val1}", m[0])
+		}
+		if m[1].Key != "key2" || m[1].Value != "val2" {
+			t.Errorf("m[1] = %+v, want {key2 val2}", m[1])
+		}
+	})
+
+	t.Run("单项", func(t *testing.T) {
+		data := []byte("only: one\n")
+		var m StrMap
+		if err := yaml.Unmarshal(data, &m); err != nil {
+			t.Fatalf("yaml.Unmarshal error = %v", err)
+		}
+		if len(m) != 1 || m[0].Key != "only" || m[0].Value != "one" {
+			t.Fatalf("m = %+v", m)
+		}
+	})
+
+	t.Run("randomInt 值保留为字符串", func(t *testing.T) {
+		data := []byte("port: randomInt(1000, 9000)\n")
+		var m StrMap
+		if err := yaml.Unmarshal(data, &m); err != nil {
+			t.Fatalf("yaml.Unmarshal error = %v", err)
+		}
+		if len(m) != 1 || m[0].Value != "randomInt(1000, 9000)" {
+			t.Fatalf("m = %+v", m)
+		}
+	})
+}
+
+func TestListMapUnmarshalYAML(t *testing.T) {
+	t.Run("正常列表值", func(t *testing.T) {
+		data := []byte("users:\n  - admin\n  - root\npasses:\n  - 123\n  - 456\n")
+		var m ListMap
+		if err := yaml.Unmarshal(data, &m); err != nil {
+			t.Fatalf("yaml.Unmarshal error = %v", err)
+		}
+		if len(m) != 2 {
+			t.Fatalf("len = %d, want 2", len(m))
+		}
+		if m[0].Key != "users" || len(m[0].Value) != 2 || m[0].Value[0] != "admin" || m[0].Value[1] != "root" {
+			t.Errorf("m[0] = %+v", m[0])
+		}
+		if m[1].Key != "passes" || len(m[1].Value) != 2 || m[1].Value[0] != "123" || m[1].Value[1] != "456" {
+			t.Errorf("m[1] = %+v", m[1])
+		}
+	})
+
+	t.Run("单个列表", func(t *testing.T) {
+		data := []byte("cmd:\n  - whoami\n")
+		var m ListMap
+		if err := yaml.Unmarshal(data, &m); err != nil {
+			t.Fatalf("yaml.Unmarshal error = %v", err)
+		}
+		if len(m) != 1 || m[0].Key != "cmd" || m[0].Value[0] != "whoami" {
+			t.Fatalf("m = %+v", m)
+		}
+	})
+
+	t.Run("数字值转字符串", func(t *testing.T) {
+		data := []byte("ports:\n  - 80\n  - 443\n")
+		var m ListMap
+		if err := yaml.Unmarshal(data, &m); err != nil {
+			t.Fatalf("yaml.Unmarshal error = %v", err)
+		}
+		if m[0].Value[0] != "80" || m[0].Value[1] != "443" {
+			t.Errorf("数字未转为字符串: %+v", m[0].Value)
+		}
+	})
+}
+
+func TestStrMapUnmarshalYAML_InvalidValue(t *testing.T) {
+	// value 是嵌套 map，不是字符串，应报错
+	data := []byte("key:\n  nested: val\n")
+	var m StrMap
+	if err := yaml.Unmarshal(data, &m); err == nil {
+		t.Fatal("期望错误，实际 nil")
+	}
+}
+
+func TestListMapUnmarshalYAML_InvalidValue(t *testing.T) {
+	// value 是普通字符串而非列表，应报错
+	data := []byte("key: notalist\n")
+	var m ListMap
+	if err := yaml.Unmarshal(data, &m); err == nil {
+		t.Fatal("期望错误，实际 nil")
+	}
+}
 
 func TestNormalizeHTTPProxyURL(t *testing.T) {
 	tests := []struct {