lsps2: Restore cached payment leases

After startup discovery, refill persisted fixed-amount and variable
lease cache targets. Reuse valid leases and renegotiate only missing
or stale entries so receiving can resume promptly after restart.

Co-Authored-By: HAL 9000

Author: tnull

src/lib.rs

@@ -805,6 +805,17 @@ impl Node {
 								liquidity_logger,
 								"LSP protocols discovery complete.",
 							);
+							if let Err(error) = liquidity_handler
+								.lsps2_client()
+								.refill_cached_leases(&discovery_cm)
+								.await
+							{
+								log_error!(
+									liquidity_logger,
+									"Failed scheduling LSPS2 lease cache refills: {}",
+									error
+								);
+							}
 						}
 					}
 				}

src/liquidity/client/lsps2/mod.rs

@@ -151,6 +151,23 @@ where
 		self.cache_target_state.lock().expect("lock").targets()
 	}
 
+	pub(crate) async fn refill_cached_leases(
+		self: &Arc<Self>, connection_manager: &Arc<ConnectionManager<L>>,
+	) -> Result<(), Error> {
+		self.prune_stale_cache_targets().await?;
+		for target in self.cache_targets() {
+			match target.id {
+				LeaseCacheTargetId::Fixed { amount_msat } => {
+					self.schedule_fixed_lease_refill(amount_msat, connection_manager);
+				},
+				LeaseCacheTargetId::Variable => {
+					self.schedule_variable_lease_refill(connection_manager);
+				},
+			}
+		}
+		Ok(())
+	}
+
 	pub(crate) async fn prepare_invoice_response(
 		self: Arc<Self>, request: JitInvoiceRequest, connection_manager: Arc<ConnectionManager<L>>,
 	) -> Result<JitInvoiceResponse, Error> {