chore(viridian): update all Docker services to latest pinned releases

Update all container images to their latest stable releases with pinned
version tags (not "latest" tag for reproducibility).

Multimedia services:
- Jellyfin: 10.10.5 → 10.11.5
- Lidarr: 2.9.6.4552 → 3.1.0.4875
- Prowlarr: 1.30.2.4939 → 2.3.0.5236
- qBittorrent: 5.0.3 → 5.1.4
- Radarr: 5.18.4.9674 → 6.0.4.10291
- Sonarr: 4.0.13.2932 → 4.0.16.2944

Services:
- OpenGist: 1.10 → 1.11.1

nixos/viridian/multimedia/qbittorrent/default.nix

@@ -5,7 +5,7 @@ in {
     # # Open-source software alternative to µTorrent
     qbittorrent = {
       autoStart = true;
-      image = "ghcr.io/hotio/qbittorrent:release-5.0.3";
+      image = "ghcr.io/hotio/qbittorrent:release-5.1.4";
       ports = [
         "${port}:8080/tcp" # WebUI
         "32372:32372/tcp" # Transport protocol