chore: Nix, mise, CI configuration (#129)

* chore: update Nix flake and setup mise for toolchains

* ci: use workflows

default.nix

@@ -1,16 +1,13 @@
-{
-  pkgs ? import <nixpkgs> { },
+{ pkgs ? import (fetchTarball {
+    url = "https://github.com/NixOS/nixpkgs/archive/77ef7a29d276c6d8303aece3444d61118ef71ac2.tar.gz";
+    sha256 = "0pm4l48jq8plzrrrisimahxqlcpx7qqq9c99hylmf7p3zlc3phsy";
+  }) {},
 }:
 
 pkgs.mkShell rec {
-  buildInputs = [
+  buildInputs = with pkgs; [
     # Tools
-    pkgs.git
-    pkgs.gh
-
-    # Node
-    pkgs.nodejs
-    pkgs.nodejs.pkgs.pnpm
+    pkgs.mise
 
     # Electron
     (pkgs.writeShellScriptBin "electron-nix" ''
@@ -29,5 +26,15 @@ pkgs.mkShell rec {
     pkgs.flatpak-builder
     pkgs.elfutils
     # flatpak remote-add --if-not-exists --user flathub https://dl.flathub.org/repo/flathub.flatpakrepo
+    
+    (writeShellScriptBin "fish" ''
+      exec ${pkgs.fish}/bin/fish -C 'mise activate fish | source' "$@"
+    '')
   ];
+
+  shellHook = ''
+    export ELECTRON_OVERRIDE_DIST_PATH="${pkgs.electron}/bin"
+    export MISE_NODE_COMPILE=false
+    eval "$(mise activate bash)"
+  '';
 }