feat: Enhance Go SDK with New Account Features

[armando-rodriguez-cko]

feat: Enhance Go SDK with New Account Features

Description:

This PR introduces enhancements to the Checkout SDK for Go, focusing on the accounts and payment services. Key updates include additional models, endpoints, and improved test coverage for onboarding, sub-entity operations, and payment handling.

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Key Changes:

Accounts Service:

1. New Types & Constants:

   • Added support for OnboardingStatus, BusinessType, EntityRoles, and multiple document-related types.
   • New helper functions for generating identifiers and random data (GenerateRandomBusinessRegistrationNumber, GenerateRandomString, etc.).

2. Methods:

   • CreateEntity: Creates a new entity with expanded details for businesses, individuals, and representatives.
   • GetSubEntityMembers: Retrieves members of a sub-entity.
   • ReinviteSubEntityMember: Sends a re-invitation request for a sub-entity member.
   • RetrievePaymentInstrumentDetails, UpdatePaymentInstrumentDetails: New payment instrument operations.
   • SubmitFile, UploadFile, RetrieveFile: File operations for documents.

3. Enhanced Structures:

   • Updated the Company, Representative, Documents, and ProcessingDetails structures to include more attributes such as roles, addresses, and financial details.

4. Test Improvements:

   • Expanded test cases for hosted payments and payment requests.
   • Skipped tests marked with t.Skip("unavailable").

Test Suite Enhancements:

1. Added new integration tests for account and sub-entity operations.
2. Introduced a CustomHttpClient for testing different schema versions.
3. Refined test helpers for random data generation and client setup.

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Impact:

• Increased Functionality: Support for detailed account creation and management.
• Enhanced Test Coverage: Ensures robust functionality across new API features.
• Backward Compatibility: No breaking changes introduced; existing methods maintain compatibility.

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Testing:

• Verified successful creation, retrieval, and updating of entities and payment instruments.
• Confirmed API responses match expected behavior for both success and error scenarios.