Deprecate repository — PhoneNumberKit has moved to the organization

[bguidolim]

Marks this repository as deprecated and points users to the new home.

Changes

• @available(*, deprecated, message:) on the public initializers of every standalone entry point, so any consumer is warned regardless of which API they use:
  • Core → github.com/PhoneNumberKit/PhoneNumberKit: PhoneNumberUtility, PartialFormatter, PhoneNumberFormatter
  • UI → github.com/PhoneNumberKit/PhoneNumberKitUI: PhoneNumberTextField (×4 inits), CountryCodePickerViewController
  • Init-level (not type-level) to keep the warning at consumers' construction sites and avoid flooding builds with internal-reference warnings.
• README banner explaining the move (core → PhoneNumberKit 5.0.0+, UI → PhoneNumberKitUI 1.0.0+) with migration steps; credits Roy Marmelstein.
• Freeze metadata automation — removes update_metadata.yml (stops the 12h PR cycle on this frozen repo).
• Podspec → 4.3.0 for consistency with the planned tag.

Builds clean (warnings only); 119 tests pass.

After merge (manual)

• Tag + release 4.3.0 so SPM users receive the deprecation warnings.
• pod trunk deprecate PhoneNumberKit for CocoaPods users.
• Pin a '📦 PhoneNumberKit has moved' issue.

The new packages are live and CI-green: PhoneNumberKit 5.0.0, PhoneNumberKitUI 1.0.0.