 Version 6.16.2

* catch exceptions in youtube channel search
* improved responsiveness and efficiency
	* in search and online search, ensure uncompleted search is cancelled before a new search
	* in Subscriptions, on sort or filter, ensure uncompleted task is cancelled before a new task
	* in FeedEpisodes and Episodes, existing load job is also cancelled when a new request arrives
* action bar of Preference activity is done in Compose
* restructured screen functions in Preference activity
* updated AGP to 8.7.3
