feat(firmware): add Mongoose client implementation for OCPP communication

hardware/firmware/lib/MicroOcppMongoose/src/MicroOcppMongooseClient_c.h

@@ -0,0 +1,51 @@
+// matth-x/MicroOcppMongoose
+// Copyright Matthias Akstaller 2019 - 2024
+// GPL-3.0 License (see LICENSE)
+
+#ifndef MO_MONGOOSECLIENT_C_H
+#define MO_MONGOOSECLIENT_C_H
+
+#if defined(__cplusplus) && defined(ARDUINO) //fix for conflicting defitions of IPAddress on Arduino
+#include <Arduino.h>
+#include <IPAddress.h>
+#endif
+
+#include "mongoose.h"
+#include <MicroOcpp/Core/ConfigurationOptions.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct OCPP_Connection;
+typedef struct OCPP_Connection OCPP_Connection;
+
+OCPP_Connection *ocpp_makeConnection(struct mg_mgr *mgr,
+        const char *backend_url_default,   //all cstrings can be NULL
+        const char *charge_box_id_default,
+        const char *auth_key_default,
+        const char *CA_cert_default,
+        struct OCPP_FilesystemOpt fsopt);
+
+void ocpp_deinitConnection(OCPP_Connection *sock);
+
+//update WS configs. To apply the updates, call `ocpp_reloadConfigs()` afterwards
+void ocpp_setBackendUrl(OCPP_Connection *sock, const char *backend_url);
+void ocpp_setChargeBoxId(OCPP_Connection *sock, const char *cb_id);
+void ocpp_setAuthKey(OCPP_Connection *sock, const char *auth_key);
+void ocpp_setCaCert(OCPP_Connection *sock, const char *ca_cert);
+
+void ocpp_reloadConfigs(OCPP_Connection *sock);
+
+const char *ocpp_getBackendUrl(OCPP_Connection *sock);
+const char *ocpp_getChargeBoxId(OCPP_Connection *sock);
+const char *ocpp_getAuthKey(OCPP_Connection *sock);
+const char *ocpp_getCaCert(OCPP_Connection *sock);
+
+bool ocpp_isConnectionOpen(OCPP_Connection *sock);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif