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/clnrest/default.nix

@@ -11,7 +11,7 @@ rustPlatform.buildRustPackage rec {
 
   inherit (clightning) src;
 
-  cargoHash = "sha256-SjGvKeDBZzbn4TR2nbGHb3XAon0Dv4KtSlkzX+eji8c=";
+  cargoHash = "sha256-0rpr941QkDeNLQ6Se9+DbbVBCmGyU721a27XNzylpPw=";
 
   depsExtraArgs = {
     nativeBuildInputs = [ unzip ];