feat(core,app,android,ios,cli): look up new titles after every crawl, show presses and work on iOS

Metadata was only fetched after adding a share (mobile) or from the
Settings buttons (desktop), so a show or episode that turned up in an
existing share stayed bare. Every crawl is now followed by a match run
when enrichment is on; `plan` makes no requests for a library that is
already matched. A stored episode guide is fetched again when a file
newer than it has no named entry, and daily for two weeks while an
aired episode is still unnamed.

Removing a share now carries its watch state to any other share holding
the same file, `pstr remove` drops the share's catalog rows, and the app
forgets catalog rows of shares no longer configured — an older `pstr
remove` left them, and every episode showed twice.

iOS, for a slow iPad:
- swipe back on a settings page uses its own edge strip; on the whole
  page it also pressed the row under the finger and opened the metadata
  sheet
- "Change match" from the tile menu opens once the menu has dismissed,
  not after a guessed 350 ms that a slow device missed
- the activity banner tracks each running line by itself (also Android),
  so overlapping work no longer leaves it spinning forever
- buttons, tiles and rows draw their press; marking watched shows at
  once; remove/repair share, sign out and deletions show the banner;
  the player says "Opening…" while the stream opens
- posters are read into a reserved buffer instead of a byte at a time

docs/IOS.md

@@ -79,6 +79,11 @@ Each of these is the platform's doing, not a choice to diverge.
   place of Android's `WatchSyncWorker`, and every five minutes while it is open.
 - **Background audio off pauses** the episode when the app leaves the screen, where
   Android stops it.
+- **Presses are drawn by hand.** Compose's ripple shows every press; SwiftUI's
+  `.plain` button style and `onTapGesture` show none, which on a slow iPad reads as
+  a tap that missed. `PressableStyle` and `tapAndHold` (`UI/Theme/Accent.swift`)
+  stand in for the ripple, and a settings page goes back by an edge strip of its
+  own, as a title page does, where Android has the system back.
 - **Nothing is backed up**, as on Android (`allowBackup="false"`). The share
   secrets are this-device-only Keychain items, so a restored share list would
   arrive without them, and a restored `sync.json` would give two devices one sync