fuuko: Make co2 exporter more reliable

This also “fixes” a typo in the variable name.

machines/fuuko/services/co2_exporter.nix

@@ -4,5 +4,10 @@
   services.co2_exporter = {
     enable = true;
     listenAddress = "${config.sbruder.wireguard.home.address}:9672"; # uses port numer of unrelated co2 exporter to avoid 8080
+    device = "/dev/airco2ntrol";
   };
+
+  services.udev.extraRules = ''
+    ACTION=="add", SUBSYSTEM=="hidraw", ATTRS{idVendor}=="04d9", ATTRS{idProduct}=="a052", SYMLINK+="airco2ntrol"
+  '';
 }

pkgs/co2_exporter/module.nix

@@ -30,7 +30,7 @@ in
       environment = {
         CO2MONITOR_ADDRESS = cfg.listenAddress;
       } // (lib.optionalAttrs (!isNull cfg.device) {
-        CO2MONITOR_DEVICE = cfg.device;
+        CO2MOINITOR_DEVICE = cfg.device; # MOINITOR ✓
       });
       serviceConfig = {
         ExecStart = "${cfg.package}/bin/co2_exporter";