gaming: declarative Flatpak via nix-flatpak (Bolt, Sober), Heroic + Proton-GE

Add nix-flatpak flake input and modules/gaming.nix managing Flatpak
remotes/packages declaratively: Bolt (Jagex launcher for RS3/OSRS) and
Sober (Roblox). Add Heroic and hyperplay-ext, plus Proton-GE for Steam.
Drops the old imperative runescape-launcher.

configuration.nix

@@ -17,6 +17,7 @@
     ./modules/security.nix
     ./modules/power.nix
     ./modules/xray.nix
+    ./modules/gaming.nix
   ];
 
   # This value determines the NixOS release from which the default

flake.lock

@@ -98,6 +98,22 @@
         "type": "github"
       }
     },
+    "nix-flatpak": {
+      "locked": {
+        "lastModified": 1767983141,
+        "narHash": "sha256-7ZCulYUD9RmJIDULTRkGLSW1faMpDlPKcbWJLYHoXcs=",
+        "owner": "gmodena",
+        "repo": "nix-flatpak",
+        "rev": "440818969ac2cbd77bfe025e884d0aa528991374",
+        "type": "github"
+      },
+      "original": {
+        "owner": "gmodena",
+        "ref": "latest",
+        "repo": "nix-flatpak",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1776877367,
@@ -141,6 +157,7 @@
       "inputs": {
         "anotherim": "anotherim",
         "lanzaboote": "lanzaboote",
+        "nix-flatpak": "nix-flatpak",
         "nixpkgs": "nixpkgs",
         "sops-nix": "sops-nix"
       }

flake.nix

@@ -15,6 +15,7 @@
       url = "git+https://dev.narayana.im/anotherim/anotherim-desktop.git?ref=dev";
       inputs.nixpkgs.follows = "nixpkgs";
     };
+    nix-flatpak.url = "github:gmodena/nix-flatpak/?ref=latest";
   };
 
   outputs = { self, nixpkgs, ... }@inputs: {
@@ -24,6 +25,7 @@
       modules = [
         inputs.lanzaboote.nixosModules.lanzaboote
         inputs.sops-nix.nixosModules.sops
+        inputs.nix-flatpak.nixosModules.nix-flatpak
         ./configuration.nix
       ];
     };

modules/gaming.nix

@@ -0,0 +1,26 @@
+# Gaming-related configuration
+# Flatpak is managed declaratively via nix-flatpak (see flake.nix input).
+{ config, pkgs, lib, ... }:
+
+{
+  # Proton-GE for Steam (better Jagex Launcher compatibility than stock Proton).
+  # Steam itself is enabled in modules/programs.nix.
+  programs.steam.extraCompatPackages = [ pkgs.proton-ge-bin ];
+
+  services.flatpak = {
+    enable = true;
+    remotes = [
+      { name = "flathub"; location = "https://dl.flathub.org/repo/flathub.flatpakrepo"; }
+    ];
+    packages = [
+      # Bolt: Jagex-account launcher for RuneScape 3 (NXT) and OSRS / RuneLite.
+      { appId = "com.adamcake.Bolt"; origin = "flathub"; }
+      # Sober: Roblox Player runtime (Android build via Flatpak) — no native Linux client.
+      { appId = "org.vinegarhq.Sober"; origin = "flathub"; }
+    ];
+    update.auto = {
+      enable = true;
+      onCalendar = "weekly";
+    };
+  };
+}

modules/packages.nix

@@ -14,6 +14,7 @@
     "terraform"
     "packer"
     "obsidian"
+    "hyperplay-ext"
   ];
 
   # List packages installed in system profile.
@@ -66,6 +67,9 @@
     obs-studio
     inputs.anotherim.packages.${pkgs.system}.default
 
+    # Gaming
+    heroic
+
     # Development
     nodejs_20
     gnupg