build(deps): pin the stable overlay and stateVersion to 26.05

26.05 is the latest stable NixOS release as of now (26.11 is still the
in-development branch that nixos-unstable reports); the previous 25.05 pin
was a release behind.

- flake.nix / flake.lock: stable overlay tracks nixos-26.05.
- neogaia system.stateVersion and the base home.stateVersion set to 26.05
  (fresh install, so aligning to the current stable release).
- Refresh the "latest stable release" references in the project docs to
  match.

Other inputs are rolling branches (nixos-unstable, nixpkgs-unstable,
chaotic nyxpkgs-unstable) or master (home-manager, per spec), so they carry
no version to bump.

.claude/CONTEXT.md

@@ -29,5 +29,5 @@ The overlay exposing `nixpkgs-unstable` packages as `unstable.<name>`, used to p
 _Avoid_: bleeding-edge, latest
 
 **stable overlay**:
-The overlay exposing the latest stable release (`nixos-25.05`) as `stable.<name>`, used to pin an individual package to the rock-solid release from the `nixos-unstable` base.
+The overlay exposing the latest stable release (`nixos-26.05`) as `stable.<name>`, used to pin an individual package to the rock-solid release from the `nixos-unstable` base.
 _Avoid_: LTS, release channel

.claude/spec/laptop-mvi.md

@@ -46,7 +46,7 @@ The install itself is done from the NixOS live ISO by cloning the repo from my G
 - Hand-rolled flake, rewritten and trimmed; no flake-parts.
 - `Auto-loader` rewritten: recursively discovers and imports every `Module` under the modules tree without the old null-placeholder traversal hack; a single discovery helper feeds the `Host` imports. The old `nixosModules` flake output is dropped.
 - Helper lib trimmed to the `Auto-loader`, the host-builder, and the script-from-file helper. `with lib.my` replaced by explicit `inherit`s throughout. `enable` flags use the stdlib enable-option helper rather than bespoke sugar.
-- `nixos-unstable` as the base channel. An `unstable overlay` exposes `nixpkgs-unstable` packages; a `stable overlay` exposes the latest stable release (`nixos-25.05`). chaotic-nyx added as an input with its overlay and binary cache from the start.
+- `nixos-unstable` as the base channel. An `unstable overlay` exposes `nixpkgs-unstable` packages; a `stable overlay` exposes the latest stable release (`nixos-26.05`). chaotic-nyx added as an input with its overlay and binary cache from the start.
 - home-manager sourced from `nix-community`, tracking master with nixpkgs followed, integrated as a NixOS module with global packages and user packages.
 - User modelled as an explicit option defaulting to `alexion`, in `wheel`, driving the system user and the home-manager user in lockstep.
 

.claude/tasks/0001-skeleton-and-building-host.md

@@ -6,7 +6,7 @@ spec: laptop-mvi
 
 Stand up the `Skeleton` and a minimal `neogaia` `Host` that evaluates and whose system toplevel builds — the walking skeleton every later slice extends and re-verifies against.
 
-The `Skeleton` is a hand-rolled flake (no flake-parts): `nixos-unstable` base channel, an `unstable overlay` exposing `nixpkgs-unstable` as `unstable.<name>`, a `stable overlay` exposing `nixos-25.05` as `stable.<name>`, and chaotic-nyx wired as an input with its overlay and binary cache.
+The `Skeleton` is a hand-rolled flake (no flake-parts): `nixos-unstable` base channel, an `unstable overlay` exposing `nixpkgs-unstable` as `unstable.<name>`, a `stable overlay` exposing `nixos-26.05` as `stable.<name>`, and chaotic-nyx wired as an input with its overlay and binary cache.
 The helper lib is trimmed to three pieces: the `Auto-loader` (recursively discovers and imports every `Module` under `modules/` and every `Host` under `hosts/` with no null-placeholder traversal hack), the host-builder, and the script-from-file helper.
 `with lib.my` is not used — dependencies are `inherit`ed explicitly.
 The `Enable convention` uses the stdlib enable-option helper; every `Module` is imported unconditionally and guards its body with `mkIf config.modules.<path>.enable`.

flake.lock

@@ -94,16 +94,16 @@
     },
     "nixpkgs-stable": {
       "locked": {
-        "lastModified": 1767313136,
+        "lastModified": 1784280462,
-        "narHash": "sha256-16KkgfdYqjaeRGBaYsNrhPRRENs0qzkQVUooNHtoy2w=",
+        "narHash": "sha256-DtoqIqM7VkR6NxAkcLpMwmi02USwWb3JdmNGLyhthc0=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "ac62194c3917d5f474c1a844b6fd6da2db95077d",
+        "rev": "293d6abedf0478e681a4dfcfcb35b30fc796a32f",
         "type": "github"
       },
       "original": {
         "owner": "nixos",
-        "ref": "nixos-25.05",
+        "ref": "nixos-26.05",
         "repo": "nixpkgs",
         "type": "github"
       }

flake.nix

@@ -9,7 +9,7 @@
     nixpkgs-unstable.url = "github:nixos/nixpkgs/nixpkgs-unstable";
 
     # Latest stable release, reachable per-package as `stable.<name>`.
-    nixpkgs-stable.url = "github:nixos/nixpkgs/nixos-25.05";
+    nixpkgs-stable.url = "github:nixos/nixpkgs/nixos-26.05";
 
     home-manager = {
       url = "github:nix-community/home-manager";

hosts/neogaia/default.nix

@@ -8,7 +8,7 @@
 {
   imports = [ ./hardware-configuration.nix ];
 
-  system.stateVersion = "25.05";
+  system.stateVersion = "26.05";
 
   boot.loader.systemd-boot.enable = true;
   boot.loader.efi.canTouchEfiVariables = true;

system/default.nix

@@ -77,7 +77,7 @@ in
       users.${user.name} = {
         home.username = user.name;
         home.homeDirectory = "/home/${user.name}";
-        home.stateVersion = "25.05";
+        home.stateVersion = "26.05";
       };
     };
   };