backup: migrate to native services.restic.backups

Replace custom backup-helper flake input with NixOS native
services.restic.backups module for ha1, monitoring01, and nixos-test1.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

hosts/monitoring01/configuration.nix

@@ -57,15 +57,35 @@
   services.qemuGuest.enable = true;
 
   sops.secrets."backup_helper_secret" = { };
-  backup-helper = {
-    enable = true;
-    password-file = "/run/secrets/backup_helper_secret";
-    backup-dirs = [
-      "/var/lib/grafana/plugins"
+  services.restic.backups.grafana = {
+    repository = "rest:http://10.69.12.52:8000/backup-nix";
+    passwordFile = "/run/secrets/backup_helper_secret";
+    paths = [ "/var/lib/grafana/plugins" ];
+    timerConfig = {
+      OnCalendar = "daily";
+      Persistent = true;
+    };
+    pruneOpts = [
+      "--keep-daily 7"
+      "--keep-weekly 4"
+      "--keep-monthly 6"
+      "--keep-within 1d"
     ];
-    backup-commands = [
-      # "grafana.db:${pkgs.sqlite}/bin/sqlite /var/lib/grafana/data/grafana.db .dump"
-      "grafana.db:${pkgs.sqlite}/bin/sqlite3 /var/lib/grafana/data/grafana.db .dump"
+  };
+
+  services.restic.backups.grafana-db = {
+    repository = "rest:http://10.69.12.52:8000/backup-nix";
+    passwordFile = "/run/secrets/backup_helper_secret";
+    command = [ "${pkgs.sqlite}/bin/sqlite3" "/var/lib/grafana/data/grafana.db" ".dump" ];
+    timerConfig = {
+      OnCalendar = "daily";
+      Persistent = true;
+    };
+    pruneOpts = [
+      "--keep-daily 7"
+      "--keep-weekly 4"
+      "--keep-monthly 6"
+      "--keep-within 1d"
     ];
   };