feat(base): add nix store garbage collection and boot entry limits

modules/base/default.nix

@@ -1,6 +1,7 @@
 # Base configuration shared across all systems
 {
   imports = [
+    ./gc.nix
     ./nix-config.nix
     ./unfree-packages.nix
   ];

modules/base/gc.nix

@@ -0,0 +1,18 @@
+# Nix store garbage collection
+{
+  lib,
+  pkgs,
+  ...
+}: {
+  nix.gc =
+    {
+      automatic = true;
+      options = "--delete-older-than 30d";
+    }
+    // lib.optionalAttrs pkgs.stdenv.isLinux {
+      dates = "weekly";
+    }
+    // lib.optionalAttrs pkgs.stdenv.isDarwin {
+      interval = {Weekday = 0;};
+    };
+}

modules/nixos/boot.nix

@@ -0,0 +1,4 @@
+# Limit boot entries to prevent /boot from filling up
+{
+  boot.loader.systemd-boot.configurationLimit = 10;
+}

modules/nixos/default.nix

@@ -3,6 +3,7 @@
   imports = [
     ./llm
     ./web
+    ./boot.nix
     ./filebrowser-quantum.nix
     ./restic-backup.nix
     ./users.nix