v3.4.0

Highlights (v3.4.0)

• Expanded Direct Post v2 coverage with advanced optional fields:
  • EPS_RESULTPARAMS
  • EPS_CALLBACKPARAMS
  • EPS_CARDSCHEME (MCR routing hint)
  • EPS_SURCHARGEENABLED
  • EPS_SURCHARGEAMOUNT
  • EPS_SURCHARGERATE
  • EPS_SURCHARGEFEE
• Improved Direct Post fingerprint generation to include optional documented fields when present.
• Enhanced Store-only flow:
  • adds EPS_STORE=true
  • supports EPS_STORETYPE (default TOKEN)
  • store-specific fingerprint behavior covered by tests.
• Added stricter UnionPay (UPOP) validation:
  • allows only AUD/CNY currencies
  • rejects risk-management transaction mode
  • rejects EMV 3DS transaction mode
• Documentation upgrades:
  • clearer flow selection in README.md
  • updated ARCHITECTURE.md
  • expanded docs/feature-matrix.md
  • expanded docs/features-implemented-tree.md
• Quality status:
  • PHPUnit passing (72 tests, 258 assertions)
  • PHPStan clean (No errors)

Upgrade Notes

• No intended breaking changes to Omnipay gateway names or core flow methods.
• Existing integrations should continue to work.
• New behavior is additive, except stricter UPOP validation now fails fast for invalid combinations.