Add Missing Document Types

[armando-rodriguez-cko]

Add Missing Document Types

Description:

This PR introduces support for additional document types in the Checkout.com SDK, improving coverage for specific compliance and verification scenarios.

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Key Changes:

Documents.cs

• Added two new document properties for EEA Sole Trader (3.0) representatives:
  • ProofOfResidentialAddress
  • ProofOfRegistration

ProofOfRegistration.cs

• Added a new document class:
  • Properties:
    • Type: Specifies the type of proof (e.g., trade register extract).
    • Front: Stores the document data.

ProofOfRegistrationType.cs

• Defined an enum for ProofOfRegistration types:
  • ExtractFromTradeRegister
  • Other

ProofOfResidentialAddress.cs

• Added a new document class:
  • Properties:
    • Type: Specifies the type of residential address proof.
    • Front: Stores the document data.

ProofOfResidentialAddressType.cs

• Defined an enum for ProofOfResidentialAddress types:
  • ProofOfAddress

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Impact:

• Improved Compliance: Supports additional document types required for EEA Sole Trader verifications.
• Expanded Use Cases: Enables better handling of regional and compliance-specific document verification workflows.

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Additional Notes:

• These changes align with the latest compliance updates for EEA verification.
• The new fields and enums are backward compatible and optional.