feat: add Irish locale (en_IE) support

[florinel-chis]

Summary

• Adds new en_IE locale with providers for Person, Address, PhoneNumber, Internet, and Payment
• Person: Irish first names (Gaelic: Sean, Aoife, Cian, Niamh, etc. + anglicised) and surnames including O-prefixed (O'Sullivan, O'Brien, O'Connor) and Mc/Mac names (McCarthy, McGrath, McLoughlin)
• Address: Eircode generation using real routing key prefixes (D01-D24 for Dublin, plus nationwide area codes), 26 traditional counties with Co. prefix, and 55+ real Irish cities/towns
• PhoneNumber: Irish landline formats with real area codes (+353 1 Dublin, +353 21 Cork, etc.) and mobile prefixes (083, 085, 086, 087, 089)
• Internet: Irish TLDs (.ie, .co.ie)
• Payment: Irish IBAN (IE country code)

Test plan

• All 11 new en_IE tests pass (84 assertions)
• Full test suite passes (1427 tests)
• Smoke tested with Factory::create('en_IE') producing realistic Irish data