fix(framework): Add Gcash to PaymentMethodType to PaymentMethod Mapping

[Vani-1107]

Description

Add Gcash to PaymentMethodType to PaymentMethod Mapping

Motivation and Context

Earlier the refunds were failing with the below error : Invalid data format: payment_method_type. This payment method type cannot be mapped to a high-level category

This is because of missing mapping of Gcash.

Additional Changes

• This PR modifies the API contract
• This PR modifies application configuration/environment variables

How did you test it?

1. Complete a payment
2. Refund for Dlocal (Gcash):

Request:

curl --location 'http://localhost:8080/refunds' \
--header 'Content-Type: application/json' \
--header 'Accept: application/json' \
--header 'api-key: dev_VZiFyyIr3ysG38QSE8tKkXmPHvUqb9AenOZ7PKroSyqpkLjk5JLBg1nBl9jfjfO2' \
--data '{
    "payment_id": "pay_j6qwv1u44BlSkKErSjRQ",
    "amount": 100,
    "reason": "Customer returned product",
    "refund_type": "instant",
    "all_keys_required": true
}'

Response:

{
    "refund_id": "ref_svnoMiBlAMcIEG1Vu6hU",
    "payment_id": "pay_j6qwv1u44BlSkKErSjRQ",
    "amount": 100,
    "currency": "PHP",
    "status": "failed",
    "reason": "Customer returned product",
    "metadata": null,
    "error_message": null,
    "error_code": null,
    "unified_code": null,
    "unified_message": null,
    "created_at": "2026-08-14T08:00:21.220Z",
    "updated_at": "2026-08-14T08:00:21.959Z",
    "connector": "dlocal",
    "profile_id": "pro_J9UurJpIif1UKKGQt1gD",
    "merchant_connector_id": "mca_jdk57GPxewi8t3eRmtxD",
    "split_refunds": null,
    "issuer_error_code": null,
    "issuer_error_message": null,
    "raw_connector_response": null,
    "connector_refund_id": "REF-1454629-x1l7tiol-248blo00n17pd2-4d4satcjgrvc"
}

This resulted in failure because of issue at connectors end. Have raised it with dlocal team