feat: user domain -- errors

pkg/validate/phone/validate.go

@@ -0,0 +1,15 @@
+package phone
+
+import (
+	"backend/pkg/errors"
+	"regexp"
+)
+
+func IsValid(value string) (bool, error) {
+	re := regexp.MustCompile(`^(?:0|\+98|0098)(\d{10})$`)
+	result := re.FindStringSubmatch(value)
+	if len(result) > 0 {
+		return true, nil
+	}
+	return false, errors.ErrPhoneInvalid
+}