feat(editors): restore vscode alongside zed for build123d workflows

- linux: programs.vscode via pkgs-master with gnome-libsecret password store
- darwin: visual-studio-code cask + aerospace window rules
- idols-ai: persist .vscode and .config/Code (Settings Sync handles extensions)
- xdg: code.desktop editor association and vscode:// scheme handler

home/linux/gui/base/vscode.nix

@@ -0,0 +1,21 @@
+{
+  lib,
+  pkgs-master,
+  ...
+}:
+
+{
+  programs.vscode = {
+    # Extensions and settings are managed by VS Code's built-in Settings Sync,
+    # not declaratively here (persisted via `.config/Code`, see preservation).
+    enable = true;
+    package = pkgs-master.vscode.override {
+      commandLineArgs = [
+        # https://code.visualstudio.com/docs/configure/settings-sync#_recommended-configure-the-keyring-to-use-with-vs-code
+        # For use with any package that implements the Secret Service API
+        # (for example gnome-keyring, kwallet5, KeepassXC)
+        "--password-store=gnome-libsecret"
+      ];
+    };
+  };
+}