feat(renovate): update schedules to Saturday afternoon

- lockFileMaintenance: Saturday 2-4pm (was Monday 5am)
- nix-stable-ecosystem: Saturday 2-4pm
- nix-unstable-ecosystem: Saturday 2-4pm
- Add nixpkgs-qt rule: Saturday 4-6pm (staggered)

This allows CI builds to run overnight Saturday→Sunday, with human
review Saturday evening and builds complete by Sunday morning.

Closes: x-ymkgu

flake.lock

@@ -258,22 +258,6 @@
         "type": "github"
       }
     },
-    "nixpkgs-qt": {
-      "locked": {
-        "lastModified": 1770464364,
-        "narHash": "sha256-z5NJPSBwsLf/OfD8WTmh79tlSU8XgIbwmk6qB1/TFzY=",
-        "owner": "nixos",
-        "repo": "nixpkgs",
-        "rev": "23d72dabcb3b12469f57b37170fcbc1789bd7457",
-        "type": "github"
-      },
-      "original": {
-        "owner": "nixos",
-        "ref": "nixos-25.11",
-        "repo": "nixpkgs",
-        "type": "github"
-      }
-    },
     "nixpkgs-unstable": {
       "locked": {
         "lastModified": 1769170682,
@@ -363,7 +347,6 @@
         "nix-darwin": "nix-darwin",
         "nix-doom-emacs-unstraightened": "nix-doom-emacs-unstraightened",
         "nixpkgs": "nixpkgs",
-        "nixpkgs-qt": "nixpkgs-qt",
         "nixpkgs-unstable": "nixpkgs-unstable",
         "perles": "perles",
         "plasma-manager": "plasma-manager",

flake.nix

@@ -4,9 +4,6 @@
   inputs = {
     nixpkgs.url = "github:nixos/nixpkgs/nixos-25.11";
     nixpkgs-unstable.url = "github:nixos/nixpkgs/nixos-unstable";
-    # Separate nixpkgs for qt5webengine-dependent packages (jellyfin-media-player, etc.)
-    # Updates on separate Renovate schedule to avoid massive qt rebuilds
-    nixpkgs-qt.url = "github:nixos/nixpkgs/nixos-25.11";
 
     nix-darwin = {
       url = "github:nix-darwin/nix-darwin/nix-darwin-25.11";
@@ -79,11 +76,6 @@
         config.allowUnfree = true;
         overlays = unstableOverlays;
       };
-      # Separate nixpkgs for qt5webengine-heavy packages to avoid rebuild churn
-      qt-pinned = import inputs.nixpkgs-qt {
-        system = prev.stdenv.hostPlatform.system;
-        config.allowUnfree = true;
-      };
       custom = prev.callPackage ./packages {};
       # Compatibility: bitwarden renamed to bitwarden-desktop in unstable
       bitwarden-desktop = prev.bitwarden-desktop or prev.bitwarden;

roles/common.nix

@@ -23,13 +23,7 @@
         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 = {