fix: pay invoice status (#2481)

* fix: rest `pay_invoice` pending instead of failed
* fix: rpc `pay_invoice` pending instead of failed
* fix: return "failed" value for payment
* fix: handle failed status for LNbits funding source
* chore: `phoenixd` todo
* test: fix condition
* fix: wait for payment status to be updated
* fix: fail payment when explicit status provided

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Co-authored-by: dni ⚡ <office@dnilabs.com>

lnbits/wallets/base.py

@@ -70,14 +70,11 @@ class PaymentStatus(NamedTuple):
         return self.paid is False
 
     def __str__(self) -> str:
-        if self.paid is True:
-            return "settled"
-        elif self.paid is False:
+        if self.success:
+            return "success"
+        if self.failed:
             return "failed"
-        elif self.paid is None:
-            return "still pending"
-        else:
-            return "unknown (should never happen)"
+        return "pending"
 
 
 class PaymentSuccessStatus(PaymentStatus):