Use PSRAM for MQTT publishing and make it scheduled (#2113)

* Run the Homeassistant Discovery directly after connecting to the broker. Before it was delayed 10s and happened while the first round alredy was in progress

* schedule sending HA discovery and static topics

* Allow setting QOS for MQTT topics

* .

* .

* change MQTT QOS1 expiration time from (default) 30 to 5s

* add logging of heap change on MQTT topic sendings

* wait for MQTT transmission timeout after publishing

* use QOS0 for Homeassistant Discovery topics. the messages then could possibly get lost but we save a lot of heap

* .

* use PSRAM for the MQTT outbox

* use QOS1 for HA discovery again

* .

* .

* disable delay, not needed with PSRAM

* .

* consolidated scheduledSendingOf_DiscoveryAndStaticTopics into sendingOf_DiscoveryAndStaticTopics_scheduled

* Send Homeasstsiatnt Discovery and static data in MQTT step instead of when the wifi gets connected

* "WIFI roaming" by channel scan (AP switching at low RSSI) (#2120)

* Activate 802.11kv wifi mesh roaming

* Activate roaming by scanning

* Revert stack reducation

* move Wifi, LWIP and BSSI to PSRAm

* added State Class "measurement" to rate_per_time_unit (#2116)

Co-authored-by: CaCO3 <caco@ruinelli.ch>

* use QOS0 for Homeassistant Discovery topics. the messages then could possibly get lost but we save a lot of heap

* use QOS0 for Homeassistant Discovery topics. the messages then could possibly get lost but we save a lot of heap

# Conflicts:
#	code/components/jomjol_mqtt/server_mqtt.cpp

# Conflicts:
#	code/components/jomjol_mqtt/server_mqtt.cpp

* .

* .

* move to next PR

* Update code/components/jomjol_mqtt/server_mqtt.cpp

* Update code/components/jomjol_mqtt/server_mqtt.cpp

---------

Co-authored-by: CaCO3 <caco@ruinelli.ch>
Co-authored-by: Slider0007 <115730895+Slider0007@users.noreply.github.com>

code/components/jomjol_mqtt/mqtt_outbox.h

@@ -0,0 +1,66 @@
+/* This is an adaption of https://github.com/espressif/esp-mqtt/blob/master/lib/include/mqtt_outbox.h
+ * This file is subject to the terms and conditions defined in
+ * file 'LICENSE', which is part of this source code package.
+ * Tuan PM <tuanpm at live dot com>
+ */
+#ifndef _MQTT_OUTOBX_H_
+#define _MQTT_OUTOBX_H_
+//#include "platform.h"
+#include "esp_err.h"
+
+#ifdef  __cplusplus
+extern "C" {
+#endif
+
+struct outbox_item;
+
+typedef struct outbox_list_t *outbox_handle_t;
+typedef struct outbox_item *outbox_item_handle_t;
+typedef struct outbox_message *outbox_message_handle_t;
+typedef long long outbox_tick_t;
+
+typedef struct outbox_message {
+    uint8_t *data;
+    int len;
+    int msg_id;
+    int msg_qos;
+    int msg_type;
+    uint8_t *remaining_data;
+    int remaining_len;
+} outbox_message_t;
+
+typedef enum pending_state {
+    QUEUED,
+    TRANSMITTED,
+    ACKNOWLEDGED,
+    CONFIRMED
+} pending_state_t;
+
+outbox_handle_t outbox_init(void);
+outbox_item_handle_t outbox_enqueue(outbox_handle_t outbox, outbox_message_handle_t message, outbox_tick_t tick);
+outbox_item_handle_t outbox_dequeue(outbox_handle_t outbox, pending_state_t pending, outbox_tick_t *tick);
+outbox_item_handle_t outbox_get(outbox_handle_t outbox, int msg_id);
+uint8_t *outbox_item_get_data(outbox_item_handle_t item,  size_t *len, uint16_t *msg_id, int *msg_type, int *qos);
+esp_err_t outbox_delete(outbox_handle_t outbox, int msg_id, int msg_type);
+esp_err_t outbox_delete_msgid(outbox_handle_t outbox, int msg_id);
+esp_err_t outbox_delete_msgtype(outbox_handle_t outbox, int msg_type);
+esp_err_t outbox_delete_item(outbox_handle_t outbox, outbox_item_handle_t item);
+int outbox_delete_expired(outbox_handle_t outbox, outbox_tick_t current_tick, outbox_tick_t timeout);
+/**
+ * @brief Deletes single expired message returning it's message id
+ *
+ * @return msg id of the deleted message, -1 if no expired message in the outbox
+ */
+int outbox_delete_single_expired(outbox_handle_t outbox, outbox_tick_t current_tick, outbox_tick_t timeout);
+
+esp_err_t outbox_set_pending(outbox_handle_t outbox, int msg_id, pending_state_t pending);
+pending_state_t outbox_item_get_pending(outbox_item_handle_t item);
+esp_err_t outbox_set_tick(outbox_handle_t outbox, int msg_id, outbox_tick_t tick);
+int outbox_get_size(outbox_handle_t outbox);
+void outbox_destroy(outbox_handle_t outbox);
+void outbox_delete_all_items(outbox_handle_t outbox);
+
+#ifdef  __cplusplus
+}
+#endif
+#endif