Calculate verification status from cross-signing sigs and update dynamically

resources/qml/UserProfile.qml

resources/qml/device-verification/DeviceVerification.qml

src/Cache.cpp

src/Cache.h

src/CacheCryptoStructs.h

src/Cache_p.h

src/timeline/TimelineModel.cpp

src/ui/UserProfile.cpp

src/ui/UserProfile.h