refactor: change to litterate config

Configuration is now held by the `.org` files. All `.nix` files are
tangled from the org-mode files.

modules/packages/appimage.nix

@@ -1,16 +1,8 @@
 {
   flake.modules.nixos.appimage = {
-    lib,
-    config,
-    ...
-  }:
-    with lib; let
-      cfg = config.mySystem.packages.appimage;
-    in {
-      options.mySystem.packages.appimage.enable = mkEnableOption "Enables AppImage support";
-      config.programs.appimage = mkIf cfg.enable {
-        inherit (cfg) enable;
-        binfmt = true;
-      };
+    programs.appimage = {
+      enable = true;
+      binfmt = true;
     };
+  };
 }

modules/packages/appimage.org

@@ -0,0 +1,24 @@
+#+title: AppImage
+#+setupfile: ../headers
+
+* AppImage
+A small module to let AppImages run directly, without having to
+extract or wrap them by hand first. Here’s the =nixos.appimage= module.
+#+begin_src nix :tangle yes
+{
+  flake.modules.nixos.appimage = {
+    <<enable-appimage>>
+  };
+}
+#+end_src
+
+=binfmt= registers AppImages with the kernel’s =binfmt_misc=, so running
+one is as simple as executing it directly, the same as any other
+binary.
+#+name: enable-appimage
+#+begin_src nix
+programs.appimage = {
+  enable = true;
+  binfmt = true;
+};
+#+end_src

modules/packages/flatpak.nix

@@ -8,11 +8,8 @@
     with lib; let
       cfg = config.mySystem.packages.flatpak;
     in {
-      options.mySystem.packages.flatpak = {
-        enable = mkEnableOption "Enable Flatpak support";
-        builder.enable = mkEnableOption "Enable Flatpak builder";
-      };
-      config = mkIf cfg.enable {
+      options.mySystem.packages.flatpak.builder.enable = mkEnableOption "Enable Flatpak builder";
+      config = {
         environment.systemPackages = lists.optional cfg.builder.enable pkgs.flatpak-builder;
         services.flatpak.enable = true;
       };