feat(meta,core,app,android,ios): AniSkip where files have no chapters

Most files that are not fansub releases carry no chapters, so they had no
skip button. AniSkip knows where an episode's opening and ending are, by
MyAnimeList id and episode number. ani.zip sends each entry's MyAnimeList
id and enrichment now keeps it on every episode row; schema v14 adds the
column and marks AniList titles un-enriched, deleting nothing, as v13 did.

When a file has loaded with no chapter naming an opening or ending, and
its length is known, each client asks once, with enrichment on only. The
answer lives as long as the file is open. with_skip_ranges cuts it into
the chapters as chapters named Opening and Ending, so the skip button,
auto-skip, the up-next countdown and the seek bar's marks all work
through the code a chaptered file uses. A file's own opening or ending
always wins over AniSkip's.

PRIVACY.md lists what is sent: the MyAnimeList id, the episode number and
the file's length.

android/app/src/androidTest/java/io/narl/protonstream/native/UniFfiBoundaryTest.kt

@@ -102,7 +102,7 @@ class UniFfiBoundaryTest {
      */
     @Test
     fun chapterPlanningCrossesTheBoundaryIntact() {
-        val plan = chapterPlan(emptyList(), 1560.0)
+        val plan = chapterPlan(emptyList(), 1560.0, emptyList())
         assertNotNull(plan)
         assertNull(skipOffer(plan, 12.0))
     }

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

@@ -19,6 +19,7 @@ import java.util.concurrent.locks.ReentrantLock
 import kotlin.concurrent.withLock
 import uniffi.pstr_android.ChapterPlan
 import uniffi.pstr_android.ChapterRecord
+import uniffi.pstr_android.SkipRangeRecord
 import uniffi.pstr_android.SubtitleFilesRecord
 import uniffi.pstr_android.SubtitleTrackRecord
 import uniffi.pstr_android.chapterPlan
@@ -135,6 +136,8 @@ class NativeMpvHost private constructor(private val nativeHandle: Long) : Libmpv
     @Volatile private var currentMedia: String? = null
     @Volatile private var currentGeneration: Double = -1.0
     @Volatile private var plannedFor: Pair<Double, Long>? = null
+    /** What AniSkip said about the open episode, keyed by that episode. */
+    @Volatile private var skipRanges: Pair<String, List<SkipRangeRecord>>? = null
     /** The load generation whose subtitle pick has been looked at. */
     @Volatile private var subtitlesCheckedFor: Double = -1.0
     var onPlaybackStarted: (() -> Unit)? = null
@@ -226,6 +229,7 @@ class NativeMpvHost private constructor(private val nativeHandle: Long) : Libmpv
                             mutableTracks.value = emptyList()
                             mutableChapters.value = ChapterPlan(emptyList(), null)
                             plannedFor = null
+                            skipRanges = null
                         }
                     }
                 } ?: false
@@ -268,6 +272,17 @@ class NativeMpvHost private constructor(private val nativeHandle: Long) : Libmpv
     }
 
     fun seek(position: Double) { withOpenHandle { nativeSeek(it, position) } }
+
+    /**
+     * Take AniSkip's answer for [media], and plan the chapters again with it.
+     * Dropped when another episode has opened since it was asked for.
+     */
+    fun setSkipRanges(media: String, ranges: List<SkipRangeRecord>) {
+        if (media != currentMedia) return
+        skipRanges = media to ranges
+        plannedFor = null
+        refreshChapters(mutableState.value)
+    }
     fun setVolume(volume: Double) { withOpenHandle { nativeVolume(it, volume) } }
     fun setMuted(muted: Boolean) { withOpenHandle { nativeMute(it, muted) } }
 
@@ -394,7 +409,8 @@ class NativeMpvHost private constructor(private val nativeHandle: Long) : Libmpv
             }
         }.onSuccess { chapters ->
             plannedFor = wanted
-            mutableChapters.value = chapterPlan(chapters, state.duration.takeIf { it > 0.0 })
+            val skips = skipRanges?.takeIf { it.first == currentMedia }?.second.orEmpty()
+            mutableChapters.value = chapterPlan(chapters, state.duration.takeIf { it > 0.0 }, skips)
         }
     }
 

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

@@ -125,6 +125,7 @@ import kotlinx.coroutines.delay
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import uniffi.pstr_android.ChapterEntry
+import uniffi.pstr_android.ChapterKind
 import uniffi.pstr_android.EpisodeRecord
 import uniffi.pstr_android.TitleRecord
 import uniffi.pstr_android.TrackPreferencesRecord
@@ -425,6 +426,20 @@ fun PlayerScreen(
         if (autoSkip && !state.paused && skipped.add(chapter.index)) nativeHost.seek(target)
     }
 
+    // A file whose chapters name no opening or ending asks AniSkip, once, when
+    // its length is known. Only with posters and descriptions on: anything
+    // else, an error included, leaves the file as its chapters made it.
+    val lengthKnown = playingThis && state.duration > 0.0
+    LaunchedEffect(key, lengthKnown) {
+        if (!lengthKnown) return@LaunchedEffect
+        val named = chapters.entries.any { it.kind == ChapterKind.OPENING || it.kind == ChapterKind.ENDING }
+        if (named) return@LaunchedEffect
+        val ranges = runCatching {
+            NativeRuntime.engine().skipTimes(titleKey, episode.shareId, episode.linkId, state.duration)
+        }.getOrNull()
+        if (!ranges.isNullOrEmpty()) nativeHost.setSkipRanges(key, ranges)
+    }
+
     var landscapeLocked by remember { mutableStateOf(false) }
     // Set by the rotation button: from then on the viewer decides.
     var rotationChosen by remember { mutableStateOf(false) }