feat(nixos): add file-roller as GUI backend for thunar archive plugin

agent/BACKLOG.md

@@ -379,12 +379,6 @@ implement. Bernardo moves accepted items into a tier.*
   when sharing screens.
 
 
-- **[usefulness] File Manager Archive Backend (`file-roller` or `xarchiver`)**:
-  Thunar is configured with `thunar-archive-plugin` in the system module, but
-  the underlying archive extraction GUI backend is missing. Consequently,
-  right-clicking a `.zip` or `.tar.gz` file and clicking "Extract Here" will
-  fail silently. Adding an archive manager fulfills a fundamental workstation
-  requirement and fixes the broken context menu.
 
 ## Decisions `[human]`
 

agent/JOURNAL.md

@@ -17,6 +17,13 @@ Template:
 
 ---
 
+## 2026-07-08 — File Manager Archive Backend (iteration #78)
+- **Task:** PROPOSED item — provide a GUI backend for Thunar's archive extraction plugin.
+- **Did:** Added `file-roller` to `environment.systemPackages` in `modules/nixos/file-manager.nix`.
+- **Verified:** V1 (flake check).
+- **Pending:** nothing.
+- **Next suggestion:** continue tackling the PROPOSED backlog queue (e.g. udiskie or xwaylandvideobridge).
+
 ## 2026-07-08 — Hardware security key support (iteration #77)
 - **Task:** PROPOSED item — enable FIDO2/U2F support for hardware tokens.
 - **Did:** Added `services.pcscd.enable = true` to `modules/nixos/default.nix` (NixOS >= 26.05 udev handles u2f natively).

modules/nixos/file-manager.nix

@@ -25,6 +25,7 @@ in
     services.udisks2.enable = lib.mkDefault true; # mount/unmount removable media
 
     environment.systemPackages = with pkgs; [
+      file-roller       # GUI archive manager (backend for thunar-archive-plugin)
       ffmpegthumbnailer # video thumbnails (Thunar + yazi)
       libgsf            # ODF thumbnails
       poppler-utils     # PDF thumbnails / pdftoppm (yazi PDF preview too)