chore: replace PhoneNormalizer with OpenEMR's PhoneNumber value object

[kojiromike]

The module has a hand-rolled PhoneNormalizer::toE164() that uses regex-based normalization. OpenEMR core now provides OpenEMR\Common\ValueObjects\PhoneNumber, a proper value object backed by libphonenumber with:

• PhoneNumber::tryParse() / PhoneNumber::parse() — robust parsing with region support
• ->toE164() — proper E.164 formatting
• ->isValid() / ->isPossible() — validation against real area codes
• ->toNational(), ->toInternational(), ->toHL7() — multiple format outputs

Also relevant: OpenEMR\Common\Utils\ValidationUtils::isValidPhoneNumber() for validation-only checks.

Steps

1. Replace all PhoneNormalizer::toE164() call sites with PhoneNumber::tryParse()?->toE164()
2. Consider passing PhoneNumber value objects through the service layer instead of raw E.164 strings
3. Remove PhoneNormalizer class and its tests
4. Verify libphonenumber is available at runtime via OpenEMR (no new Composer dependency needed)

[kojiromike]

Blocked: OpenEMR\Common\ValueObjects\PhoneNumber was introduced in openemr/openemr#10326 (2026-01-27) which is only on master — not in any released version. The module currently pins to >=8.0.0 and the installed version (8.0.0) doesn't include the ValueObjects directory or libphonenumber.

This is unblocked once the next OpenEMR version ships with the PhoneNumber class, or when we bump the minimum version constraint to dev-master / 8.1.0.