When pay is xpay: listsendpays needs amount_msat too, just like listpays

[hMsats]

v24.11

First (558) paid with xpay, second (559) with pay.

Output from listsendpays

      {
         "created_index": 558,
         "id": 558,
         "payment_hash": "492d22ec7a5b13bcf8b8c3097bd0be6bf21c8c094f587cc525ed9ee56109dad0",
         "groupid": 1831353814669324182,
         "updated_index": 479,
         "partid": 1,
         "amount_sent_msat": 103000,
         "created_at": 1733897213,
         "completed_at": 1733897214,
         "status": "complete",
         "payment_preimage": "b13b6dc35925bc5b5ce7124ed696f335fefc4f2f67902e3919ef32963beddca0",
         "bolt12": "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"
      },
      {
         "created_index": 559,
         "id": 559,
         "payment_hash": "4efaa101fd27890870602adcfc3b3d0404af66cfcd83e1746ed2073b38711d11",
         "groupid": 1,
         "updated_index": 480,
         "destination": "031979fe6ce0e69ece6d99a4bc4a7b30ed22a8cb8703dd7dd2dfaf619e07127e0b",
         "amount_msat": 103000,
         "amount_sent_msat": 103000,
         "created_at": 1733897315,
         "completed_at": 1733897316,
         "status": "complete",
         "payment_preimage": "c1171033ebfd191e755a5d27c8f7168f57e3f5bff662924f4f6e2d14ebfeaaf0",
         "bolt12": "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"
      }

[hMsats]

For now I put in pay.c:

/*
        if (amount_msat_greater(t->msatoshi, AMOUNT_MSAT(0)))
                json_add_amount_msat(response, "amount_msat", t->msatoshi);
*/
        json_add_amount_msat(response, "amount_msat", t->msatoshi_sent);

because t->msatoshi is 0 for some reason when pay is xpay and that made spark-wallet great again

[rustyrussell]

This is similar to #7881

[hMsats]

Solved via #7941