Address review: retry-latch hygiene on subscriber change, parity note

- Both retry latches clear on subscribe/unsubscribe: a new subscriber
  must not receive a connected=false for an address from the previous
  session (it resyncs through its own subscribe requests)
- The app-register failure path states its BLEClientBase parity so the
  no-retry behavior reads as deliberate

esphome/components/bluetooth_connection/bluetooth_connection_bluedroid.cpp

@@ -58,6 +58,8 @@ void BluedroidGattClient::loop() {
   }
   auto st = this->state();
   if (st == ClientState::INIT) {
+    // Parity with BLEClientBase: a failed registration marks the slot
+    // failed and idles it without retry.
     auto ret = esp_ble_gattc_app_register(this->app_id);
     if (ret) {
       ESP_LOGE(TAG, "gattc app register failed: app_id=%d code=%d", this->app_id, ret);

esphome/components/bluetooth_proxy/bluetooth_proxy.cpp

@@ -620,6 +620,9 @@ void BluetoothProxy::subscribe_api_connection(api::APIConnection *api_connection
              api_connection->get_peername_to(new_peername), this->api_connection_->get_name(),
              this->api_connection_->get_peername_to(old_peername));
   }
+  // Stale retry latches belong to the previous subscriber's session.
+  this->connections_free_pending_ = false;
+  this->pending_disconnection_address_ = 0;
   this->api_connection_ = api_connection;
 #ifdef USE_BLE_SCANNER_STATE_CALLBACK
   // get_scanner_state() is part of the push-hub surface (see BLEHubContract).
@@ -635,6 +638,8 @@ void BluetoothProxy::unsubscribe_api_connection(api::APIConnection *api_connecti
     return;
   }
   this->api_connection_ = nullptr;
+  this->connections_free_pending_ = false;
+  this->pending_disconnection_address_ = 0;
 }
 
 void BluetoothProxy::send_device_connection(uint64_t address, bool connected, uint16_t mtu, conn_err_t error) {