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.
UIActivityViewController is presented as a popover on iPad and requires an
anchor; without a sourceView/barButtonItem UIKit aborts in
-[UIPopoverPresentationController presentationTransitionWillBegin]. Set
sourceView/sourceRect on both the direct presentation in the swipe-actions
modifier and the ShareSheet representable.
Fixes a SIGABRT seen in TestFlight build 261.
Convert detail and filter sheets to shared helpers, add inline Filter /
Export / Clear buttons next to the search bar (toolbar items weren't
surfacing in the settings detail pane), inline the Reset Filters button
at the bottom of the filter sheet, use a 'Close' text button, and trim
the macOS Share Sheet to just the scrollable log with a Copy button.
