feat: handle []string or string for pathAlias

template/yaml_types.go

@@ -0,0 +1,31 @@
+package template
+
+import "errors"
+
+type StringOrSlice []string
+
+func (s *StringOrSlice) UnmarshalYAML(unmarshal func(any) error) error {
+	var single string
+	if err := unmarshal(&single); err == nil {
+		if single == "" {
+			*s = nil
+			return nil
+		}
+		*s = []string{single}
+		return nil
+	}
+
+	var multi []string
+	if err := unmarshal(&multi); err == nil {
+		*s = multi
+		return nil
+	}
+
+	var nothing *struct{}
+	if err := unmarshal(&nothing); err == nil {
+		*s = nil
+		return nil
+	}
+
+	return errors.New("expected string, []string, or null")
+}