Add nix-flatpak system

flake.nix

@@ -17,6 +17,9 @@
     home-manager.url = "github:nix-community/home-manager/release-25.11";
     home-manager.inputs.nixpkgs.follows = "nixpkgs";
 
+    # Nix Flatpak
+    nix-flatpak.url = "github:gmodena/nix-flatpak/?ref=latest";
+
     # Nix Homebrew
     nix-homebrew.url = "github:zhaofengli/nix-homebrew";
     homebrew-core.url = "github:homebrew/homebrew-core";
@@ -32,6 +35,7 @@
       nix-darwin,
       flake-parts,
       import-tree,
+      nix-flatpak,
       home-manager,
       nix-homebrew,
       homebrew-core,
@@ -65,6 +69,7 @@
               ]
               ++ [
                 (import-tree ./overlays/nixos)
+                nix-flatpak.nixosModules.nix-flatpak
                 home-manager.nixosModules.home-manager
 
                 (import-tree ./hosts/common)

modules/system/nixos/apps/flatpak.nix

@@ -1,49 +0,0 @@
-{
-  lib,
-  pkgs,
-  config,
-  ...
-}:
-with lib;
-let
-  grep = pkgs.gnugrep;
-  cfg = config.os.flatpak.apps;
-  flatpaks = [
-    "com.usebottles.bottles"
-    "io.github.flattool.Warehouse"
-  ];
-in
-{
-  options.os.flatpak.apps = {
-    enable = mkEnableOption "System gnome apps service";
-  };
-  config = mkIf cfg.enable {
-
-    services.flatpak.enable = true;
-    system.userActivationScripts.flatpakManagement = {
-      text = ''
-
-        ${pkgs.flatpak}/bin/flatpak remote-add --if-not-exists fedora oci+https://registry.fedoraproject.org
-
-        installedFlatpaks=$(${pkgs.flatpak}/bin/flatpak list --app --columns=application)
-
-        for installed in $installedFlatpaks; do
-          if ! echo ${toString flatpaks} | ${grep}/bin/grep -q $installed; then
-            echo "Suppression de $installed car il n'est pas dans la liste desiredFlatpaks."
-            ${pkgs.flatpak}/bin/flatpak uninstall -y --noninteractive $installed
-          fi
-        done
-
-        for app in ${toString flatpaks}; do
-          echo "Vérification que $app est installé."
-          ${pkgs.flatpak}/bin/flatpak install -y flathub $app
-        done
-
-        ${pkgs.flatpak}/bin/flatpak uninstall --unused -y
-        ${pkgs.flatpak}/bin/flatpak update -y
-
-      '';
-    };
-
-  };
-}