Which has more correct nullability for some methods and case insensitivity for listFiles where possible.
(cherry picked from commit a74a689c9048cc67f4854678fbfefa361631a5e7)
# Conflicts:
# app/src/main/java/eu/kanade/tachiyomi/data/download/Downloader.kt
# source-local/src/androidMain/kotlin/tachiyomi/source/local/image/LocalCoverManager.kt
c2d2295149