[BUG] Creating payment larger than balance has sentAmount larger than balance

[sidvishnoi]

Steps to reproduce

1. Have an account with balance, say €10.
2. With create an outgoing payment grant with amount larger than balance, say €20.
3. Create an outgoing payment with debitAmount larger than account balance but within grant limit.

   {
     "incomingPayment": "https://ilp.interledger-test.dev/incoming-payments/...",
     "walletAddress": "https://ilp.interledger-test.dev/...",
     "debitAmount": {
       "value": "1500",
       "assetCode": "EUR",
       "assetScale": 2
     }
   }

4. Poll for GET /outgoing-payments/{ID}.

Expected result

sentAmount should not go beyond account balance. Outgoing payment should fail soon enough.

Actual result

    "sentAmount": {
        "value": "1485",
        "assetCode": "EUR",
        "assetScale": 2
    }

Transactions page shows outgoing payment in pending. Incoming payment shows completed!

Sending another payment (say €4) works fine after this still (within grant limit; but more than should-be remaining balance).

Screenshots or videos

In screenshot: sent €15 from EUR to MXN; then sent €4 to MXN. €10 is initial deposit (last txn from bottom).

Additional context

As seen in WM extension. Created grant budget larger than account balance, then sent €15, €4 payments. Both marked as successful as polling outgoing-payment showed amount being sent.

Operating system

Windows, macOS, Linux

Operating system version

No response

Browsers

Chrome, Microsoft Edge, Firefox

Browser version

No response