Many changes

modules/fish/default.nix

@@ -0,0 +1,4 @@
+{ ... }: {
+  # Although we are configuring fish in home manager, this is needed for vendor completions within fish.
+  programs.fish.enable = true;
+}

modules/fish/home.nix

@@ -0,0 +1,16 @@
+{ pkgs, ... }: {
+  home.packages = [
+    pkgs.grc
+    pkgs.fishPlugins.grc
+  ];
+
+  programs.fish = {
+    enable = true;
+    interactiveShellInit = ''
+      set fish_greeting  # Disable greeting
+    '';
+    shellAliases = {
+      l = "ls -lh";
+    };
+  };
+}