Rerun CI after the runner's nix image was pinned

The previous runs died on the runner, not in the code: its nix-store
volume no longer matched nixos/nix:latest. The runner now uses
nixos/nix:2.35.3 with a volume seeded from that image.

Assisted-by: Claude:opus-5-5

CLAUDE.md

@@ -25,6 +25,12 @@ Content is edited in the asxp.io admin (`/admin/bingo`, repo `asxpio`:
   are provisioned by the `storage` repo (`init/`), from the same
   `BINGO_*` secrets set on both repos.
 
+## Research
+
+Before adding or changing datacenters, incidents or photos, follow
+`OSINT.md`. It covers sources, verification, photo rules (no people, and
+renderings only for unbuilt sites) and credit format.
+
 ## Layout
 
 - `app.rb`: `BingoWeb`. Routes: `/` (redirect by Accept-Language), `/ru|en|uk`