Teardown bluetooth phoneAPI better and fix client notification issue (#4834)

* Teardown bluetooth phoneAPI better and fix client notification issue

* Fix client notification draining

src/mesh/PhoneAPI.h

@@ -147,11 +147,6 @@ class PhoneAPI
      */
     virtual void onNowHasData(uint32_t fromRadioNum) {}
 
-    /**
-     * Subclasses can use this to find out when a client drops the link
-     */
-    virtual void handleDisconnect();
-
   private:
     void releasePhonePacket();
 
@@ -159,6 +154,8 @@ class PhoneAPI
 
     void releaseMqttClientProxyPhonePacket();
 
+    void releaseClientNotification();
+
     /// begin a new connection
     void handleStartConfig();