chore(packages): retrait des outils perso et reliquats associés

Nextcloud est désormais utilisé sur une autre machine. Retrait du client
et des packages perso inutilisés (brave, signal, calibre, beancount…).

Reliquats nettoyés :
- i3 : autostart nextcloud
- zsh : complétion k3d, variables Cypress (binaire Nix supprimé)

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

programs/zsh.nix

@@ -74,7 +74,6 @@
 
       # K8s
       source <(helm completion zsh)
-      source <(k3d completion zsh)
       source <(kubectl completion zsh)
       source <(k9s completion zsh); compdef _k9s k9s
 
@@ -103,11 +102,7 @@
       ZSH_AUTOSUGGEST_HIGHLIGHT_STYLE = "fg=7";
       TERMINAL = "sakura";
       PATH = "$PATH:$HOME/.npm/bin:$HOME/.local/bin";
-      # Use a local Cypress binary instead of the one installed by the CLI (not usable on NixOS)
-      # see https://github.com/NixOS/nixpkgs/pull/56387 and https://discourse.nixos.org/t/cypress-with-npm/15137/4
       HUSKY = 0;
-      CYPRESS_INSTALL_BINARY = 0;
-      CYPRESS_RUN_BINARY = "$HOME/.nix-profile/bin/Cypress";
       LD_LIBRARY_PATH = "${pkgs.libgcc}/lib";
     };