Delete declarations that Periphery reports unused on every platform that
compiles them (iOS, macOS, tvOS), including nine views used only by their
own previews. Platform-gated code still used on another platform, device-
only MPV render paths, migration models, CloudKit record names, App
Intents metadata and unused parameters are kept.
Proxied thumbnail URLs from Invidious/Piped/Yattee server expire over
time. Two paths were left holding stale URLs: the Video Info carousel
kept the original list copy even after fresh details arrived, and
downloaded videos rendered from the remote URL snapshot taken at
download time while the local thumbnail on disk was ignored.
Evict stale URLs from the Nuke cache when fresh video details load,
pass the fresh details through to the videoCard thumbnail, and resolve
downloads' thumbnails from the local file when localThumbnailPath is
set.
