Merge branch 'polecat/shiny/x-qdkuu@mlec8nfv': add harmonia cache to nix.settings

Configure all NixOS machines to use the internal harmonia binary cache:
- Add nix-cache.johnogle.info as substituter
- Add harmonia signing public key to trusted-public-keys
- Enable fallback for local builds when cache unreachable
- Set 5s connect-timeout for faster fallback

Refs: x-qdkuu

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

roles/common.nix

@@ -23,7 +23,13 @@
         max-jobs = "auto";
         trusted-users = [ "johno" ];
         substituters = [
+          "https://nix-cache.johnogle.info"
         ];
+        trusted-public-keys = [
+          "nix-cache.johnogle.info-1:IC5x8BxnrqkU9XqhMdDnZLtSg9Y3rBJVXhve5DJ92J0="
+        ];
+        fallback = true;
+        connect-timeout = 5;
       };
 
       gc = {

roles/kodi/default.nix

@@ -47,23 +47,23 @@ in
       if cfg.jellyfinScaleFactor != null
       then pkgs.symlinkJoin {
         name = "jellyfin-media-player-scaled";
-        paths = [ pkgs.jellyfin-media-player ];
+        paths = [ pkgs.qt-pinned.jellyfin-media-player ];
         nativeBuildInputs = [ pkgs.makeWrapper ];
         postBuild = ''
           mkdir -p $out/bin
           rm -f $out/bin/jellyfin-desktop
-          makeWrapper ${pkgs.jellyfin-media-player}/bin/jellyfin-desktop $out/bin/jellyfin-desktop \
+          makeWrapper ${pkgs.qt-pinned.jellyfin-media-player}/bin/jellyfin-desktop $out/bin/jellyfin-desktop \
             --add-flags "--tv --scale-factor ${toString cfg.jellyfinScaleFactor}"
 
           # Update .desktop file to include scale factor and TV mode arguments
           mkdir -p $out/share/applications
           rm -f $out/share/applications/org.jellyfin.JellyfinDesktop.desktop
-          substitute ${pkgs.jellyfin-media-player}/share/applications/org.jellyfin.JellyfinDesktop.desktop \
+          substitute ${pkgs.qt-pinned.jellyfin-media-player}/share/applications/org.jellyfin.JellyfinDesktop.desktop \
             $out/share/applications/org.jellyfin.JellyfinDesktop.desktop \
             --replace-fail "Exec=jellyfin-desktop" "Exec=jellyfin-desktop --tv --scale-factor ${toString cfg.jellyfinScaleFactor}"
         '';
       }
-      else pkgs.jellyfin-media-player;
+      else pkgs.qt-pinned.jellyfin-media-player;
   in mkIf cfg.enable
     {
       users.extraUsers.kodi = {