chore(nix): bump nixpkgs 24.05 → 24.11

Three breakages handled:

- hardware.opengl → hardware.graphics (renamed in 24.11). Touches
  upboard.nix, douro.nix, batm3.nix, live.nix.
- vaapiIntel dropped — legacy pre-Broadwell driver, removed in
  nixpkgs. UP Board (Cherry Trail) and OptiPlex 9030 (Haswell) both
  use intel-media-driver, which stays.
- vaapiVdpau renamed → libva-vdpau-driver.

system.stateVersion stays 24.05 — convention is to never bump after
install. Existing Sintra and fresh flashes keep the 24.05 state
semantics; that's correct.

All 8 nixosConfigurations (4 models × {live,installed}) evaluate
clean with zero deprecation warnings on 24.11.

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

deploy/nixos/README.md

@@ -9,7 +9,7 @@ NixOS module + tooling for deploying bitSpire to ATM hardware (Sintra, tejo, dou
 ```
 deploy/nixos/
 ├── bitspire-atm.nix        # NixOS module: services.bitspire option tree + systemd unit + udev rules
-├── configuration.nix       # Base system (NixOS 24.05, locale, kernel, packages, bitspire user)
+├── configuration.nix       # Base system (NixOS 24.11, locale, kernel, packages, bitspire user)
 ├── live.nix                # Live USB variant (squashfs + tmpfs root) — used by mkLiveConfig
 ├── hardware/
 │   ├── douro.nix           # Dell OptiPlex 9030 AIO (stock Douro motherboard; SATA SSD, eGalax touch)