activationScripts: rewrite /etc/nixos with configuration source

configuration.nix

@@ -2,7 +2,6 @@
 {
   imports = [
     ./variables-module.nix
-    ./files.nix
     ./volumes.nix
     ./users.nix
     ./letsencrypt/acme.nix

files.nix

@@ -1,4 +1,4 @@
-{ config, pkgs, ... }:
+nixos-config-source: { config, pkgs, ... }:
 let
   cfg = config.selfprivacy;
   dnsCredentialsTemplates = {
@@ -29,6 +29,10 @@ in
       nixos-lustrate = ''
         rm -rf /old-root
       '';
+      selfprivacy-nixos-configuration-source = ''
+        rm -rf /etc/nixos/{*,.[!.]*}
+        cp -r --no-preserve=all ${nixos-config-source}/ -T /etc/nixos/
+      '';
       cloudflareCredentials = ''
         mkdir -p /var/lib/cloudflare
         chmod 0440 /var/lib/cloudflare

flake.nix

@@ -24,6 +24,7 @@
           modules = [
             hardware-configuration
             ./configuration.nix
+            (import ./files.nix top-level-flake.outPath)
             (import ./userdata-variables.nix userdata)
             selfprivacy-api.nixosModules.default
             {