chore: bump HTLC_EXPIRY_THRESHOLD_SECS from 10 to 45

The 10s threshold was too tight for the webhook delivery pipeline,
causing premature HTLC expiry and RetriesExhausted failures on
402 payments. 45s gives ample room for webhook round-trips while
still well within CLTV delta bounds.

Author: martinsaposnic

lightning-liquidity/src/lsps4/service.rs

@@ -49,7 +49,7 @@ use std::string::String;
 use std::time::Instant;
 use std::vec::Vec;
 
-const HTLC_EXPIRY_THRESHOLD_SECS: u64 = 10;
+const HTLC_EXPIRY_THRESHOLD_SECS: u64 = 45;
 
 /// Action to forward a specific HTLC through a channel
 #[derive(Debug)]