fix(idempotency): serialize Pydantic models with mode='json' for UUID/date support

[abhu85]

Issue number: closes #8065

Summary

Changes

The _prepare_data() function in aws_lambda_powertools/utilities/idempotency/base.py was calling model_dump() without specifying mode="json", which defaults to mode="python". This caused Pydantic models containing UUIDs, dates, or datetimes to fail with "Object of type UUID is not JSON serializable" error when used with @idempotent_function.

Fix: Changed data.model_dump() to data.model_dump(mode="json") to ensure proper JSON serialization of UUID, date, and datetime fields.

User experience

Before:

from uuid import UUID
from pydantic import BaseModel

class PaymentInput(BaseModel):
    payment_id: UUID
    customer_id: str

@idempotent_function(data_keyword_argument="payment", persistence_store=persistence_layer)
def process_payment(payment: PaymentInput):
    return {"status": "processed"}

# Raises: Object of type UUID is not JSON serializable

After:

# Same code now works correctly - UUID is serialized as string for idempotency key generation
process_payment(payment=PaymentInput(payment_id=uuid4(), customer_id="123"))
# Returns: {"status": "processed"}

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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