Bug: ValidationError on unknown enum value APPROVE in TransactionResponse.operation

[choisangh]

Describe the bug
When calling get_transactions() using fireblocks-sdk version 10.1.0, a ValidationError is raised because the response includes a transaction with operation="APPROVE", which is not in the expected enum list.
This causes the SDK to fail parsing the response due to strict Pydantic validation.

To Reproduce
Steps to reproduce the behavior:

1. Call fireblocks.transactions.get_transactions()
2. Await the .result() or iterate over the response
3. SDK crashes with ValidationError from Pydantic
4. See error related to unexpected "APPROVE" value in operation

Expected behavior
The SDK should either:

• Accept "APPROVE" as a valid operation type in the enum
• Or gracefully handle unknown enum values (e.g., using a fallback, warning, or generic type)

Screenshots

ValidationError: 1 validation error for TransactionResponse
operation
  Input should be 'TRANSFER', 'BURN', 'CONTRACT_CALL', 'MINT', 'RAW', 'TYPED_MESSAGE',
  'ENABLE_ASSET', 'STAKE', 'UNSTAKE', 'WITHDRAW', 'REDEEM_FROM_COMPOUND' or
  'SUPPLY_TO_COMPOUND' [type=enum, input_value='APPROVE', input_type=str]

Versions (please complete the following information):

• Python Version: 3.10.0
• fireblocks-sdk version: 10.1.0

Additional context
The Fireblocks API appears to have added a new operation type "APPROVE" that is not yet reflected in the SDK’s enum.
Please consider updating the SDK to include it or make the enum extensible to prevent crashes when Fireblocks introduces new types.

[github-actions]

Acknowledged. We'll review the issue and respond soon.