Email address validation is too strict

[xenomote]

if the "local part" of an email address is quoted, it may contain any number of @s, white-space characters and non printable unicode characters. Those three checks should be removed from the checkEmail String validation function to prevent erroneously rejecting compliant (although admittedly very weird) email addresses:

ogen/validate/string.go

Lines 63 to 99 in 8aafb42

	func (t String) checkEmail(v string) error {
	// Pretty basic validation, but should work for most cases and is not
	// too strict to break things.
	//
	// Still better than obscure regex or std `mail.ParseAddress`.
	var (
	gotAt bool
	last rune
	)
	for i, r := range v {
	if unicode.IsSpace(r) {
	return errors.Errorf("space character (%U)", r)
	}
	if !unicode.IsPrint(r) {
	return errors.Errorf("not printable character (%U)", r)
	}
	last = r
	if r != '@' {
	continue
	}
	if gotAt {
	return errors.New(`got @ multiple times`)
	}
	if i == 0 {
	return errors.New(`got @ at start`)
	}
	gotAt = true
	}
	if last == '@' {
	return errors.New("@ at end")
	}
	if !gotAt {
	return errors.New(`no @`)
	}
	return nil
	}

additionally, you can theoretically introduce a min/max length validation according to https://www.rfc-editor.org/errata/eid1003, though that may be covered by explicitly setting minLength and maxLength