iOS CarPlay: the phone's bar takes up the car's episode; only playable shows (#442, #443, #444)

#442: a car's pick told the page `replaced`, and the page closed its player bar, so leaving the
car with the episode playing left nothing on the phone to pause it. And when the car launched the
app, the page loaded later and was never told anything played. Now the app sends `nowPlaying`
(the item, its place, playing or not) on a car pick, at the page's `ready`, and on coming
forward, and the page's bar takes it up and drives the phone's player. `replaced` is still
handled for builds before this one.

#443: Shows listed every feed with items, blogs included. Now only feeds with a downloaded file,
and an episode only with a downloaded audio file: /media/{id} answers 404 before the download.

#444: tests/native-bridge.ts read its failure count before the CarPlay checks, so those could
fail and still exit 0. The count is read last now.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RqkrVARreS9wxzH5o2rF7N

ios/CHANGELOG.md

@@ -13,7 +13,7 @@ The iOS app, `ios/`. Format: [Keep a Changelog](https://keepachangelog.com/en/1.
 - A sleep timer in the player, kept by the phone, so it pauses on time with the screen locked, fading out over the last ten seconds; and an AirPlay button beside it, for another speaker or a TV (#429).
 - iPX opens with no connection, showing the lists it last had, as it does in a browser: the page's service worker now runs in the app. This is for `ipodderx.sdf1.net` only, and links to other sites open in Safari (#435).
 - Siri and Shortcuts: "Resume iPX", "Pause iPX", "Skip forward in iPX", "Skip back in iPX", "Set a sleep timer in iPX" and "How many unread in iPX", with nothing to set up, and each an action in Shortcuts. Resume works with the app closed, carrying on with the last episode from where you left off (#427).
-- CarPlay: In Progress, Unread and Shows on the car's screen, an episode playing from where you left off and saving its place as it does on the phone, and the car's Now Playing for the rest (#420).
+- CarPlay: In Progress, Unread and Shows on the car's screen, an episode playing from where you left off and saving its place as it does on the phone, and the car's Now Playing for the rest. It lists only shows and episodes with a downloaded audio file, and the phone's player bar takes up what the car plays (#420, #442, #443).
 - A widget for the home screen and lock screen: the unread count, and the episode you were on with a button to resume or pause it (#428).
 - The icon's count stays right with the app closed: ipx sends it to the phone when it changes, once its `[push]` is set up, in place of waiting for iOS's background refresh (#433).
 - Presses are felt: a light tap on play, pause, flag and pull to refresh, a success on marking read, a warning with an error (#430).