feat(payment_charges): add support for collecting and refunding charges on payments

[kashif-m]

Type of Change

• Bugfix
• New feature
• Enhancement
• Refactoring
• Dependency updates
• Documentation
• CI/CD

Description

Detailed description - #4659

This PR adds functionality to create charges on payment intents using Stripe

• create charges on payment_intent
• store charge_id in payment_attempt
• use charge_id for refunds
  • Direct

   "charges": {
       "charge_id": "ch_3PJDz8Ihl7EEkW0O16Wetnl5",
       "revert_platform_fee": true
   }
  

  • Destination

   "charges": {
       "charge_id": "ch_3PJDz8Ihl7EEkW0O16Wetnl5",
       "revert_platform_fee": true,
       "revert_transfer": true
   }
  

Note - charges on mandates is not added in this PR.

Additional Changes

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

Motivation and Context

How did you test it?

Tested locally using postman collection.

Steps for testing

• Make sure Stripe Connect is enabled on your Stripe account
• Onboard a Standard user by initiating an account link from Stripe's dashboard
• Make sure merchant account is created and Stripe is added as a payment connector
• Create a direct charge on payment by adding below field in /payment_intents request

"charges": {
        "charge_type": "direct",
        "fees": 123,
        "transfer_account_id": "acct_1PDftAIhl7EEkW0O"
}

• Create a destination charge on payment by adding below field in /payment_intents request

"charges": {
        "charge_type": "destination",
        "fees": 123,
        "transfer_account_id": "acct_1PDftAIhl7EEkW0O"
}

Direct charges

• ref - https://docs.stripe.com/connect/direct-charges
• these help in directly creating charges when customer is paying to the connected account
• charges are created, money is split (Stripe fees + reseller’s fees) and the remaining amount is transferred to connected account’s balance

Destination charges

• ref - https://docs.stripe.com/connect/destination-charges
• charges are created on the reseller’s account
• reseller decides whether some of all of those funds are to be transferred to the connected account
• reseller’s account is used for debiting the cost of Stripe fees, refunds and chargebacks
• only supported when both reseller and connected accounts belong to the same country

Checklist

• I formatted the code cargo +nightly fmt --all
• I addressed lints thrown by cargo clippy
• I reviewed the submitted code
• I added unit tests for my changes where possible

[SamraatBansal]

LGTM! Approving on behalf of connectors

[ThisIsMani]

Dashboard specific changes looks fine.