fix(nix): refresh upstream Nix pins for 26.715.31925 (#1067)

Refreshed Codex.dmg SRI hash to sha256-xgK3kJYGqI3M5ZbZGlRCjcO1MFo/Ee+MMGDZ/tw6E5Y= and synced codexVersion / electronVersion / native-module pins to the current upstream DMG.

Verified all ChatGPT Desktop Nix package outputs against the refreshed DMG.

Source-Main-SHA: b49b4d6

Upstream-DMG-SHA256: c602b7909606a88dcce596d91a54428dc3b5305a3f11ef8c3060d9fedc3a1396

Co-authored-by: codex-dmg-hash-bot <actions@github.com>

Author: github-actions[bot]

flake.nix

@@ -94,10 +94,10 @@
 
         codexDmg = pkgs.fetchurl {
           url = "https://persistent.oaistatic.com/codex-app-prod/ChatGPT.dmg";
-          hash = "sha256-hs3FKrLBT42VNYCRIbJRLpuJE4/qr6asaXuuhxDqGds=";
+          hash = "sha256-xgK3kJYGqI3M5ZbZGlRCjcO1MFo/Ee+MMGDZ/tw6E5Y=";
         };
 
-        codexVersion = "26.715.31251";
+        codexVersion = "26.715.31925";
         electronVersion = "42.3.0";
         electronPlatform =
           {