feat: v1 release branch — generated flakes and template track ?ref=v1

Installed machines and the downstream template now resolve nomarchy from
git+https://git.bemagri.xyz/bernardo/nomarchy.git?ref=v1 (the lock's
original node carries the ref too), so `nix flake update` follows the
release branch instead of the forge's default branch. README quickstart
points at the real forge.

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

templates/downstream/flake.nix

@@ -4,8 +4,8 @@
   # The only input. nixpkgs, home-manager etc. come pinned through it —
   # tested together upstream. This file is written once (by you or the
   # installer) and never hand-edited afterwards; your machine lives in
-  # system.nix and home.nix.
-  inputs.nomarchy.url = "github:YOUR-USER/nomarchy"; # <- the distro repo
+  # system.nix and home.nix. v1 is the release branch.
+  inputs.nomarchy.url = "git+https://git.bemagri.xyz/bernardo/nomarchy.git?ref=v1";
 
   outputs = { nomarchy, ... }:
     nomarchy.lib.mkFlake {