ui: add call screen interface

- in/out animation
- switch calls in conversation tree
- basic controls over call: accept/hangup/hold
- video

Refs #67611

Change-Id: I1d302d2539cb473e27ea469781b72f44963eb0a0
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 58fd995..d838c7f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -38,6 +38,7 @@
    AccAdvancedVC.mm
    AccSecurityVC.mm
    AccountsVC.mm
+   CurrentCallVC.mm
    AudioPrefsVC.mm
    VideoPrefsVC.mm
    GeneralPrefsVC.mm
@@ -47,6 +48,7 @@
 SET(ringclient_FORMS
    MainMenu.xib
    RingWindow.xib
+   CurrentCall.xib
    GeneralPrefs.xib
    Accounts.xib
    AccGeneral.xib
@@ -62,6 +64,7 @@
 SET(ringclient_HDRS
    AppDelegate.h
    RingWindowController.h
+   CurrentCallVC.h
    ConversationsViewController.h
    PreferencesViewController.h
    AccGeneralVC.h