plugin-cln-xpay: Not redirecting pay (unknown arg \"maxfeepercent\") and overly verbose log entries

[tobomobo]

Issue and Steps to Reproduce

running v24.11 on Raspiblitz (x86 Proxmox VM)

When enabling xpay and trying to pay an invoice with Zeus, the redirect does not work because maxfeepercent is an unknown argument for xpay. Paying the same bolt11 invoice with lightning-cli xpay -k invstring=lnbc... works immediately.

Also when xpay-handle-pay is true I get the following 'spam' in my logs

getinfo output

{
"id": "XXX",
"alias": "XXX",
"color": "XXX",
"num_peers": 10,
"num_pending_channels": 0,
"num_active_channels": X,
"num_inactive_channels": 0,
"address": [
{
"type": "torv3",
"address": "XXX.onion",
"port": 9736
}
],
"binding": [
{
"type": "ipv4",
"address": "127.0.0.1",
"port": 9736
}
],
"version": "v24.11",
"blockheight": 874093,
"network": "bitcoin",
"fees_collected_msat": X,
"lightning-dir": "/home/bitcoin/.lightning/bitcoin",
"our_features": {
"init": "08a0880a8a59a1",
"node": "88a0880a8a59a1",
"channel": "",
"invoice": "02000002024100"
}
}

[tobomobo]

The additional Log entries are already being examined.

Reference: #7933

[Lagrang3]

xpay doesn't have the maxfeepercent option. To fix this, the hook that translates the call to pay into xpay must
replace the maxfeepercent into a maxfee value.
I can do this. I've just recently did this with renepay.

BTW. This is not a bug. If some arguments are not yet supported, we just let pay do the payment
instead of xpay.

[Lagrang3]

Connected to Zeus, I can pay after adding the patch #7936.
Still there is some UI detail to fix.
The payment goes through but Zeus screen shows an error screen with no message.
I think this is related to the fact that xpay does not reply with a status: complete field.

UPD. I've also added the "status" field in the response. Now I've noticed that the list of
payments shows 0 in the amount corresponding to the payments done with xpay as
reported in #7934