Add attic

Signed-off-by: Nikolaos Karaolidis <nick@karaolidis.com>

overlays/default.nix

@@ -1,6 +1,7 @@
 final: prev:
 {
   android-tools = import ./android-tools final prev;
+  attic-client = import ./attic-client final prev;
   darktable = import ./darktable final prev;
   hyprland = import ./hyprland final prev;
   mpv = import ./mpv final prev;
@@ -12,6 +13,7 @@ final: prev:
 // {
   dockerImages = prev.dockerImages or { } // {
     adguardhome = final.docker-image-adguardhome;
+    attic = final.docker-image-attic;
     authelia = final.docker-image-authelia;
     base = final.docker-image-base;
     comentario = final.docker-image-comentario;