fix(ai-cli): install current upstream Codex and Claude releases

- Pin official Codex 0.161.0 and Claude Code 2.1.292 binaries
- Preserve Codex helpers and Claude's NixOS compatibility wrapper
- Add an updater for stable upstream versions and checksums
- Document CLI updates independently of stable NixOS inputs

modules/development.nix

@@ -1,4 +1,7 @@
 { pkgs, ... }:
+let
+  aiCli = import ../packages/ai-cli.nix { inherit pkgs; };
+in
 {
   # Workstation tools only; language runtimes and SDKs belong in projects.
   environment.systemPackages = with pkgs; [
@@ -19,8 +22,8 @@
     zip
 
     # Coding assistants; authenticate separately as your normal user.
-    codex
-    claude-code
+    aiCli.codex
+    aiCli.claude-code
 
     # Infrastructure, containers, and structured data.
     ansible