[zaphod] Add QMK Support

hosts/zaphod/hardware.nix

···
     };
     wirelessRegulatoryDatabase = true;
     framework.enableKmod = false;
+    keyboard.qmk.enable = true;
+    keyboard.qmk.keychronSupport = true;
   };
   services.udev.packages = [
     pkgs.qmk-udev-rules