[bthome] Fix compilation errors and enhance StaticVector

- Add StaticVector::clear() method for resetting container
- Add StaticVector::push_back(T&&) for move semantics support (unique_ptr)
- Use esp_bt_dev_get_address() instead of esp_read_mac for BLE MAC
- Include esp_bt_device.h for Bluetooth device functions

Fixes compilation errors with StaticVector clear() and unique_ptr push_back,
and uses correct API for retrieving Bluetooth MAC address.

esphome/components/bthome/bthome.cpp

@@ -6,6 +6,7 @@
 #ifndef CONFIG_ESP_HOSTED_ENABLE_BT_BLUEDROID
 #include <esp_bt.h>
 #endif
+#include <esp_bt_device.h>
 #include <esp_bt_main.h>
 #include <esp_gap_ble_api.h>
 #include <freertos/FreeRTOS.h>
@@ -460,9 +461,8 @@ bool BTHome::encrypt_payload_(const uint8_t *plaintext, size_t plaintext_len, ui
     return false;
   }
 
-  // Get MAC address
-  uint8_t mac[6];
-  esp_read_mac(mac, ESP_MAC_BT);
+  // Get Bluetooth MAC address
+  const uint8_t *mac = esp_bt_dev_get_address();
 
   // Build nonce according to BTHome spec:
   // MAC (6 bytes) + UUID (2 bytes) + device info (1 byte) + counter (4 bytes) = 13 bytes

esphome/core/helpers.h

@@ -149,6 +149,13 @@ template<typename T, size_t N> class StaticVector {
     }
   }
 
+  // Move version for types like unique_ptr
+  void push_back(T &&value) {
+    if (count_ < N) {
+      data_[count_++] = std::move(value);
+    }
+  }
+
   // Return reference to next element and increment count (with bounds checking)
   T &emplace_next() {
     if (count_ >= N) {
@@ -159,6 +166,8 @@ template<typename T, size_t N> class StaticVector {
     return data_[count_++];
   }
 
+  void clear() { count_ = 0; }
+
   size_t size() const { return count_; }
   bool empty() const { return count_ == 0; }