Add mqtt server (mosquitto)

The config was based on the exsisting mosquitto setup.

config/hosts/mqtt/mosquitto.nix

@@ -0,0 +1,33 @@
+# Sources for this configuration:
+# - https://search.nixos.org/options?sort=relevance&type=packages&query=services.mosquitto
+# - https://mosquitto.org/man/mosquitto-conf-5.html
+# - https://winkekatze24.de
+{ ... }:
+
+{
+    services.mosquitto = {
+        enable = true;
+        persistence = true;
+
+        # set config for all listeners
+        listeners = [ {
+            settings.allow_anonymous = true;
+            omitPasswordAuth = true;
+            acl = ["topic readwrite #"];
+        } ];
+
+        bridges.winkekatz = {
+            addresses = [
+                { address = "mqtt.winkekatze24.de"; }
+            ];
+            topics = [
+                "winkekatze/allcats/eye/set in 2"
+                "winkekatze/allcats in 2"
+                "+/status out 2 winkekatze/ \"\""
+                "+/connected out 2 winkekatze/ \"\""
+            ];
+        };
+    };
+
+    networking.firewall.allowedTCPPorts = [ 1883 ];
+}