update nixpkgs

bitcoin: 30.2 -> 31.0
bitcoind: 30.2 -> 31.0
clboss: 0.15.1 -> 0.16.0
clightning: 25.12.1 -> 26.04.1
elementsd: 23.3.2 -> 23.3.3
lightning-loop: 0.31.5-beta -> 0.33.0-beta

lightning-loop 0.31.7+ blocks until lnd's chain notifier is ready
(lightninglabs/loop@bde49d7a), so the workaround sleep added in the
previous commit is no longer needed for lightning-loop. The
lightning-pool workaround stays — pool has no equivalent fix and
isn't actively maintained.

Note: nbxplorer test fails (presumed incompatibility with bitcoin 31).

pkgs/pinned.nix

@@ -5,19 +5,19 @@ pkgs: pkgsUnstable: pkgs-25_05:
     bitcoin
     bitcoind
     charge-lnd
-    clboss
     electrs
     extra-container
     fulcrum
-    lightning-loop
     lightning-pool
     lndconnect;
 
   inherit (pkgsUnstable)
     bitcoind-knots
     btcpayserver
+    clboss
     clightning
     elementsd
+    lightning-loop
     lnd;
 
   inherit pkgs pkgsUnstable pkgs-25_05;