v1.8.0: Audio 代码重构与低功耗优化 (#943)

* Reconstruct Audio Code

* Remove old IoT implementation

* Add MQTT-UDP documentation

* OTA升级失败时，可以继续使用

main/boards/common/adc_battery_monitor.cc

@@ -0,0 +1,81 @@
+#include "adc_battery_monitor.h"
+
+AdcBatteryMonitor::AdcBatteryMonitor(adc_unit_t adc_unit, adc_channel_t adc_channel, float upper_resistor, float lower_resistor, gpio_num_t charging_pin)
+    : charging_pin_(charging_pin) {
+    
+    // Initialize charging pin
+    gpio_config_t gpio_cfg = {
+        .pin_bit_mask = 1ULL << charging_pin,
+        .mode = GPIO_MODE_INPUT,
+        .pull_up_en = GPIO_PULLUP_DISABLE,
+        .pull_down_en = GPIO_PULLDOWN_DISABLE,
+        .intr_type = GPIO_INTR_DISABLE,
+    };
+    ESP_ERROR_CHECK(gpio_config(&gpio_cfg));
+
+    // Initialize ADC battery estimation
+    adc_battery_estimation_t adc_cfg = {
+        .internal = {
+            .adc_unit = adc_unit,
+            .adc_bitwidth = ADC_BITWIDTH_12,
+            .adc_atten = ADC_ATTEN_DB_12,
+        },
+        .adc_channel = adc_channel,
+        .upper_resistor = upper_resistor,
+        .lower_resistor = lower_resistor
+    };
+    adc_cfg.charging_detect_cb = [](void *user_data) -> bool {
+        AdcBatteryMonitor *self = (AdcBatteryMonitor *)user_data;
+        return gpio_get_level(self->charging_pin_) == 1;
+    };
+    adc_cfg.charging_detect_user_data = this;
+    adc_battery_estimation_handle_ = adc_battery_estimation_create(&adc_cfg);
+
+    // Initialize timer
+    esp_timer_create_args_t timer_cfg = {
+        .callback = [](void *arg) {
+            AdcBatteryMonitor *self = (AdcBatteryMonitor *)arg;
+            self->CheckBatteryStatus();
+        },
+        .arg = this,
+        .name = "adc_battery_monitor",
+    };
+    ESP_ERROR_CHECK(esp_timer_create(&timer_cfg, &timer_handle_));
+    ESP_ERROR_CHECK(esp_timer_start_periodic(timer_handle_, 1000000));
+}
+
+AdcBatteryMonitor::~AdcBatteryMonitor() {
+    if (adc_battery_estimation_handle_) {
+        ESP_ERROR_CHECK(adc_battery_estimation_destroy(adc_battery_estimation_handle_));
+    }
+}
+
+bool AdcBatteryMonitor::IsCharging() {
+    bool is_charging = false;
+    ESP_ERROR_CHECK(adc_battery_estimation_get_charging_state(adc_battery_estimation_handle_, &is_charging));
+    return is_charging;
+}
+
+bool AdcBatteryMonitor::IsDischarging() {
+    return !IsCharging();
+}
+
+uint8_t AdcBatteryMonitor::GetBatteryLevel() {
+    float capacity = 0;
+    ESP_ERROR_CHECK(adc_battery_estimation_get_capacity(adc_battery_estimation_handle_, &capacity));
+    return capacity;
+}
+
+void AdcBatteryMonitor::OnChargingStatusChanged(std::function<void(bool)> callback) {
+    on_charging_status_changed_ = callback;
+}
+
+void AdcBatteryMonitor::CheckBatteryStatus() {
+    bool new_charging_status = IsCharging();
+    if (new_charging_status != is_charging_) {
+        is_charging_ = new_charging_status;
+        if (on_charging_status_changed_) {
+            on_charging_status_changed_(is_charging_);
+        }
+    }
+}