refactor(rename): NixOS module + service + paths → bitspire

Five-file coordinated rename to give the dev-branch deploy a clean
`bitspire` namespace at the NixOS level:

  deploy/nixos/lamassu-atm.nix → deploy/nixos/bitspire-atm.nix
    - `services.lamassu-atm`           → `services.bitspire`
    - `systemd.services.lamassu-atm`   → `systemd.services.bitspire`
    - `/var/lib/lamassu-atm`           → `/var/lib/bitspire`
    - `/opt/lamassu-atm`               → `/opt/bitspire`
    - `/etc/lamassu-atm/config.env`    → `/etc/bitspire/config.env`

  flake.nix
    - module import path updated
    - `nixosModules.lamassu-atm` → `nixosModules.bitspire`
    - `system.activationScripts.lamassu-env` → `bitspire-env`
    - all activation-script paths point at /var/lib/bitspire

  deploy/nixos/configuration.nix
    - `networking.hostName = "lamassu-atm"` → `"bitspire"`

  deploy/nixos/live.nix
    - module import path updated
    - ISO name template: `lamassu-atm-<model>-live.iso` → `bitspire-<model>-live.iso`
    - activation-script name updated

  deploy/nixos/provision-atm.sh
    - data-dir paths: /var/lib/lamassu-atm → /var/lib/bitspire
    - systemctl + journalctl unit names updated

DELIBERATELY kept as `lamassu` (for now):
  - The `lamassu` UNIX user and group account. Renaming would
    require file-ownership migration scripts; the Sintra is a
    fresh flash so no existing data, but the internal user
    namespace inconsistency is acceptable.
  - LP-specific bits in provision-atm.sh (admin token, the
    `docker logs lamassu-lightning-pub` extractor) — those
    get ripped out in 3c when the script switches to LNbits.

NO migration activation script added — the Sintra flash is fresh,
production batm3/douro stay on `main` and never see this branch.
A future dev→main cutover will need a separate migration story
(rename UNIX user, move /var/lib/lamassu-atm → /var/lib/bitspire,
SSH key relocation, etc.).

Verified:
  nix eval .#nixosConfigurations.batm3-installed.config.systemd.services.bitspire.enable
    → true
  nix eval .#nixosConfigurations.bitSpire-live-sintra.config.networking.hostName
    → "bitspire"

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

flake.nix

@@ -116,10 +116,10 @@
           modules = [
             hardwareModule
             ./deploy/nixos/configuration.nix
-            ./deploy/nixos/lamassu-atm.nix
+            ./deploy/nixos/bitspire-atm.nix
             determinate.nixosModules.default
             ({ config, lib, pkgs, ... }: {
-              services.lamassu-atm = {
+              services.bitspire = {
                 enable = true;
                 appDir = "${atm-app}";
               };
@@ -186,10 +186,10 @@
               };
 
               # Env template — runtime secrets provisioned via provision-atm.sh
-              system.activationScripts.lamassu-env = ''
-                mkdir -p /var/lib/lamassu-atm
-                if [ ! -f /var/lib/lamassu-atm/.env ]; then
-                  cp ${pkgs.writeText "lamassu-atm-env-default" ''
+              system.activationScripts.bitspire-env = ''
+                mkdir -p /var/lib/bitspire
+                if [ ! -f /var/lib/bitspire/.env ]; then
+                  cp ${pkgs.writeText "bitspire-env-default" ''
                     VITE_RELAY_URL=
                     VITE_LIGHTNING_PUB_PUBKEY=
                     VITE_LIGHTNING_PUB_API_URL=
@@ -202,16 +202,16 @@
                     VITE_LAMASSU_FIAT_CODE=${fiatCode}
                     ELECTRON_FORCE_PROD=1
                     DISPLAY=:0
-                  ''} /var/lib/lamassu-atm/.env
-                  chmod 600 /var/lib/lamassu-atm/.env
-                  chown lamassu:lamassu /var/lib/lamassu-atm/.env
+                  ''} /var/lib/bitspire/.env
+                  chmod 600 /var/lib/bitspire/.env
+                  chown lamassu:lamassu /var/lib/bitspire/.env
                 fi
               '';
 
               # Override systemd service for Electron runtime
-              systemd.services.lamassu-atm = {
+              systemd.services.bitspire = {
                 serviceConfig = {
-                  EnvironmentFile = lib.mkForce "/var/lib/lamassu-atm/.env";
+                  EnvironmentFile = lib.mkForce "/var/lib/bitspire/.env";
                   Environment = "LD_LIBRARY_PATH=${pkgs.stdenv.cc.cc.lib}/lib";
                   ExecStart = lib.mkForce "${pkgs-unstable.electron}/bin/electron --no-sandbox --disable-gpu-sandbox --disable-gpu --disable-software-rasterizer --enable-logging ${atm-app}";
                   MemoryMax = lib.mkForce "1G";
@@ -230,7 +230,7 @@
                 after = [ "display-manager.service" ];
                 requires = [ "display-manager.service" ];
                 wantedBy = [ "graphical.target" ];
-                before = [ "lamassu-atm.service" ];
+                before = [ "bitspire.service" ];
                 serviceConfig = {
                   Type = "oneshot";
                   User = "lamassu";
@@ -282,8 +282,8 @@
 
       # ── Standalone NixOS module ───────────────────────────────────
 
-      nixosModules.default = import ./deploy/nixos/lamassu-atm.nix;
-      nixosModules.lamassu-atm = import ./deploy/nixos/lamassu-atm.nix;
+      nixosModules.default = import ./deploy/nixos/bitspire-atm.nix;
+      nixosModules.bitspire = import ./deploy/nixos/bitspire-atm.nix;
 
       # ── Packages (x86_64-linux only for ATM hardware) ─────────────