add test for loading from registry for all modules

internal/module/test/mqtt-client_test.go

@@ -0,0 +1,32 @@
+package module_test
+
+import (
+	"testing"
+
+	"github.com/jwetzell/showbridge-go/internal/config"
+	"github.com/jwetzell/showbridge-go/internal/module"
+)
+
+func TestMQTTClientFromRegistry(t *testing.T) {
+	registration, ok := module.ModuleRegistry["mqtt.client"]
+	if !ok {
+		t.Fatalf("mqtt.client module not registered")
+	}
+
+	moduleInstance, err := registration.New(config.ModuleConfig{
+		Type: "mqtt.client",
+		Params: map[string]any{
+			"broker":   "mqtt://localhost:1883",
+			"topic":    "test/topic",
+			"clientId": "test",
+		},
+	})
+
+	if err != nil {
+		t.Fatalf("failed to create mqtt.client module: %s", err)
+	}
+
+	if moduleInstance.Type() != "mqtt.client" {
+		t.Fatalf("mqtt.client module has wrong type: %s", moduleInstance.Type())
+	}
+}