feat(core,app,android,cli,ios): sync the library and settings, verify a share before adding it

Sync carried only watch positions, so a second device started empty. The
per-installation history file now also carries per-key registers
(pstr-core::profile): every share with its link and custom password, the
playback, appearance and metadata settings, the TMDB key, hand-picked
matches and per-title track choices. Newer updated_at wins per key, a
removal travels as an empty register, and a first sync stamps at 0 so a
fresh install takes the library the other devices have instead of
overwriting it with defaults. Volume, mute and the device-only settings
(cache budget, Wi-Fi only, background audio, hardware decoding) stay out.
The secrets live only in the end-to-end encrypted Drive file, never in
shares.json. FORMAT_VERSION stays 1; an older build ignores the registers.

Adding a share stored it before opening the link, so a first failure left a
broken entry and every retry said "already configured". add_verified opens
the link first and stores nothing on failure, and only the new share is
crawled afterwards, so another broken share cannot fail the add.

Android drops picture-in-picture: the window sized the video wrongly and
background audio already covers leaving the app.

iOS sizes the Metal drawable on every layout, so the picture no longer
stretches after a rotation or a Split View resize. Settings show a save at
once rather than after the match run, and a failed save reverts and says
why. Both phone clients gain an activity banner naming what is running, and
the add-share, metadata and change-match forms show progress and errors in
place.

android/app/src/main/java/io/narl/protonstream/playback/NativeMpvHost.kt

@@ -85,9 +85,9 @@ data class MpvPlaybackState(
 /**
  * What is on screen, for the surfaces that are not the player.
  *
- * The media session, its notification and Picture-in-Picture all have to name
- * the episode, and none of them can reach the composition that knows it. The
- * player publishes this once per episode and they read it.
+ * The media session and its notification have to name the episode, and
+ * neither can reach the composition that knows it. The player publishes this
+ * once per episode and they read it.
  */
 data class NowPlaying(
     val media: String,
@@ -134,8 +134,8 @@ class NativeMpvHost private constructor(private val nativeHandle: Long) : Libmpv
     /**
      * Where a transport outside the player sends previous/next.
      *
-     * The player owns which episode is open, so the notification, the lock
-     * screen and Picture-in-Picture cannot walk the playlist themselves. Both
+     * The player owns which episode is open, so the notification and the lock
+     * screen cannot walk the playlist themselves. Both
      * run on the main thread, which is where the player's state lives.
      */
     var onSkipPrevious: (() -> Unit)? = null

android/app/src/main/java/io/narl/protonstream/playback/PlaybackService.kt

@@ -35,7 +35,7 @@ import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withTimeoutOrNull
 
-/** Owns libmpv so audio survives Activity recreation, rotation and PiP. */
+/** Owns libmpv so audio survives Activity recreation and rotation. */
 class PlaybackService : Service() {
     inner class PlaybackBinder : Binder() {
         val host: NativeMpvHost? get() = this@PlaybackService.host

android/app/src/main/java/io/narl/protonstream/playback/PlayerScreen.kt

@@ -131,18 +131,14 @@ private val VOLUME_SLIDER_MIN_WIDTH = 600.dp
 /**
  * The player, as its own screen on the activity's own window.
  *
- * Not a dialog: a dialog window has its own insets, cannot be told to draw into
- * the display cutout, and hands Picture-in-Picture the wrong window. Owning the
- * activity window is what makes "fullscreen" mean the whole panel, notch
- * included.
+ * Not a dialog: a dialog window has its own insets and cannot be told to draw
+ * into the display cutout. Owning the activity window is what makes
+ * "fullscreen" mean the whole panel, notch included.
  *
  * [episodes] is the title's episodes in display order and [index] the one that is
  * open, which is what previous/next and autoplay walk. The index is hoisted so
  * that it survives process recreation with the rest of the navigation state —
  * this screen is destroyed and rebuilt by a dark-mode toggle like any other.
- *
- * In [inPictureInPicture] the window is a thumbnail with the system's own
- * controls over it, so this screen draws the picture and nothing else.
  */
 @Composable
 fun PlayerScreen(
@@ -150,7 +146,6 @@ fun PlayerScreen(
     episodes: List<EpisodeRecord>,
     index: Int,
     host: LibmpvHost?,
-    inPictureInPicture: Boolean,
     minimized: Boolean,
     onIndexChange: (Int) -> Unit,
     onSaveProgress: (EpisodeRecord, Double, Double, Boolean) -> Unit,
@@ -294,9 +289,8 @@ fun PlayerScreen(
         onIndexChange(target)
     }
 
-    // What the media notification, the lock screen and Picture-in-Picture show.
-    // None of them can reach this composition, and all three have to name the
-    // episode rather than the app.
+    // What the media notification and the lock screen show. Neither can reach
+    // this composition, and both have to name the episode rather than the app.
     LaunchedEffect(key, index, episodes.size, title.key) {
         nativeHost.publish(
             NowPlaying(
@@ -359,12 +353,6 @@ fun PlayerScreen(
             showControls = false
         }
     }
-    // Everything this screen draws over the picture is sized for a phone panel
-    // and unreadable in a thumbnail, and Android supplies its own transport
-    // there. Leaving PiP must find the controls up rather than mid-timeout.
-    val overlays = !inPictureInPicture
-    LaunchedEffect(inPictureInPicture) { if (!inPictureInPicture) showControls = true }
-
     if (minimized) return
 
     Box(
@@ -374,7 +362,6 @@ fun PlayerScreen(
             .clickable(
                 interactionSource = remember { MutableInteractionSource() },
                 indication = null,
-                enabled = overlays,
                 onClick = { showControls = !showControls },
             ),
     ) {
@@ -393,7 +380,7 @@ fun PlayerScreen(
         )
 
         AnimatedVisibility(
-            visible = overlays && showControls,
+            visible = showControls,
             modifier = Modifier.align(Alignment.TopStart),
             enter = fadeIn(),
             exit = fadeOut(),
@@ -450,7 +437,7 @@ fun PlayerScreen(
         }
 
         AnimatedVisibility(
-            visible = overlays && showControls,
+            visible = showControls,
             modifier = Modifier.align(Alignment.BottomCenter),
             enter = fadeIn(),
             exit = fadeOut(),
@@ -476,7 +463,7 @@ fun PlayerScreen(
         // Drawn whether or not the rest of the controls are up: an opening lasts
         // ninety seconds, and a button you have to wake with a tap is one nobody
         // reaches in time.
-        offer?.takeIf { overlays && !autoSkip }?.let { skip ->
+        offer?.takeIf { !autoSkip }?.let { skip ->
             TonalButton(
                 onClick = { nativeHost.seek(skip.target) },
                 modifier = Modifier
@@ -488,7 +475,7 @@ fun PlayerScreen(
 
         UpNextCard(
             next = next,
-            visible = overlays && autoplay && !state.paused &&
+            visible = autoplay && !state.paused &&
                 chapters.creditsStart?.let { state.position >= it } == true,
             onPlayNow = { advance() },
             modifier = Modifier