chore: add the nix stuffs for GHC 9.4

I've just added naively the different nix lines. The configuration file
comes from a copy of the one for 9.2.

With that, we can open a shell with `nix develop
.\#haskell-language-server-941-dev` and type `cabal build`.

(cherry picked from commit 48084ab)

configuration-ghc-94.nix

@@ -0,0 +1,42 @@
+{ pkgs, inputs }:
+
+let
+  disabledPlugins = [
+    "hls-hlint-plugin"
+    # That one is not technically a plugin, but by putting it in this list, we
+    # get it removed from the top level list of requirement and it is not pull
+    # in the nix shell.
+    "shake-bench"
+  ];
+
+  hpkgsOverride = hself: hsuper:
+    with pkgs.haskell.lib;
+    {
+      hlsDisabledPlugins = disabledPlugins;
+      # YOLO
+      mkDerivation = args:
+        hsuper.mkDerivation (args // {
+          jailbreak = true;
+          doCheck = false;
+        });
+    } // (builtins.mapAttrs (_: drv: disableLibraryProfiling drv) {
+      # ptr-poker breaks on MacOS without SSE2 optimizations
+      # https://github.com/nikita-volkov/ptr-poker/issues/11
+      ptr-poker = hself.callCabal2nix "ptr-poker" inputs.ptr-poker { };
+
+      ghc-exactprint =
+        hself.callCabal2nix "ghc-exactprint" inputs.ghc-exactprint-150 { };
+      # Hlint is still broken
+      hlint = doJailbreak (hself.callCabal2nix "hlint" inputs.hlint { });
+
+      stylish-haskell = appendConfigureFlag  hsuper.stylish-haskell "-fghc-lib";
+
+      # Re-generate HLS drv excluding some plugins
+      haskell-language-server =
+        hself.callCabal2nixWithOptions "haskell-language-server" ./.
+        (pkgs.lib.concatStringsSep " " [ "-fpedantic" "-f-hlint" ]) { };
+    });
+in {
+  inherit disabledPlugins;
+  tweakHpkgs = hpkgs: hpkgs.extend hpkgsOverride;
+}

flake.nix

@@ -215,6 +215,7 @@
 
         ghc902Config = (import ./configuration-ghc-90.nix) { inherit pkgs inputs; };
         ghc924Config = (import ./configuration-ghc-92.nix) { inherit pkgs inputs; };
+        ghc941Config = (import ./configuration-ghc-94.nix) { inherit pkgs inputs; };
 
         # GHC versions
         # While HLS still works fine with 8.10 GHCs, we only support the versions that are cached
@@ -224,11 +225,13 @@
           cases = {
             ghc902 = ghc902Config.tweakHpkgs (pkgs.hlsHpkgs "ghc902");
             ghc924 = ghc924Config.tweakHpkgs (pkgs.hlsHpkgs "ghc924");
+            ghc941 = ghc941Config.tweakHpkgs (pkgs.hlsHpkgs "ghc941");
           };
           in { default = cases."${ghcVersion}"; } // cases;
 
         ghc902 = supportedGHCs.ghc902;
         ghc924 = supportedGHCs.ghc924;
+        ghc941 = supportedGHCs.ghc941;
         ghcDefault = supportedGHCs.default;
 
         # For markdown support
@@ -361,19 +364,22 @@
           haskell-language-server-dev = mkDevShell ghcDefault "cabal.project";
           haskell-language-server-902-dev = mkDevShell ghc902 "cabal.project";
           haskell-language-server-924-dev = mkDevShell ghc924 "cabal.project";
+          haskell-language-server-941-dev = mkDevShell ghc941 "cabal.project";
         };
 
         # Developement shell, haskell packages are also provided by nix
         nixDevShells = {
           haskell-language-server-dev-nix = mkDevShellWithNixDeps ghcDefault "cabal.project";
           haskell-language-server-902-dev-nix = mkDevShellWithNixDeps ghc902 "cabal.project";
           haskell-language-server-924-dev-nix = mkDevShellWithNixDeps ghc924 "cabal.project";
+          haskell-language-server-941-dev-nix = mkDevShellWithNixDeps ghc941 "cabal.project";
         };
 
         allPackages = {
           haskell-language-server = mkExe ghcDefault;
           haskell-language-server-902 = mkExe ghc902;
           haskell-language-server-924 = mkExe ghc924;
+          haskell-language-server-941 = mkExe ghc941;
         };
 
         devShells = simpleDevShells // nixDevShells // {