Merge pull request 'Playlist-track atomic replace + ci-requirements true-up' (#115) from dev into main

`refreshDetail` did an un-transacted `deleteByPlaylist` + `upsertAll` — the
same shape as the Home index write that #2327 just fixed. Room's
InvalidationTracker fires after the DELETE, so an observer of
`observeByPlaylist` would see `emptyList()` before the new rows land, which is
exactly what made every Home row visibly collapse to empty and refill.

Nothing consumes `observeByPlaylist` today, so this is not a live defect — it's
a landmine. Making playlist detail cache-first later would have silently
reintroduced the flicker, and the reason would have been three layers away from
the symptom. One `@Transaction` now costs nothing and removes that.

`deleteByPlaylist` is left in place as the building block but is no longer
called from outside the DAO.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

android/app/src/main/java/com/fabledsword/minstrel/cache/db/dao/CachedPlaylistTrackDao.kt

@@ -4,6 +4,7 @@ import androidx.room.Dao
 import androidx.room.Insert
 import androidx.room.OnConflictStrategy
 import androidx.room.Query
+import androidx.room.Transaction
 import com.fabledsword.minstrel.cache.db.entities.CachedPlaylistTrackEntity
 import kotlinx.coroutines.flow.Flow
 
@@ -35,10 +36,33 @@ interface CachedPlaylistTrackDao {
     @Query("SELECT MAX(position) FROM cached_playlist_tracks WHERE playlistId = :playlistId")
     suspend fun maxPosition(playlistId: String): Int?
 
-    /** Replace-all pattern for a playlist; called after a sync delta lands. */
     @Query("DELETE FROM cached_playlist_tracks WHERE playlistId = :playlistId")
     suspend fun deleteByPlaylist(playlistId: String)
 
+    /**
+     * Replaces a playlist's whole membership in ONE transaction; called
+     * after a refresh or a sync delta lands.
+     *
+     * Atomic on purpose. Room's InvalidationTracker only notifies observers
+     * after the transaction commits, so [observeByPlaylist] never sees the
+     * empty gap between the delete and the re-insert. Un-transacted, that
+     * gap is a real observed state — it's what made every Home row visibly
+     * collapse to empty and refill before issue #2327 fixed the equivalent
+     * write in `CachedHomeIndexDao`.
+     *
+     * Nothing observes [observeByPlaylist] live today, so this is
+     * pre-emptive: it means making playlist detail cache-first later can't
+     * silently reintroduce that flicker.
+     */
+    @Transaction
+    suspend fun replacePlaylistTracks(
+        playlistId: String,
+        rows: List<CachedPlaylistTrackEntity>,
+    ) {
+        deleteByPlaylist(playlistId)
+        if (rows.isNotEmpty()) upsertAll(rows)
+    }
+
     @Query(
         "DELETE FROM cached_playlist_tracks " +
             "WHERE playlistId = :playlistId AND trackId IN (:trackIds)",

android/app/src/main/java/com/fabledsword/minstrel/playlists/data/PlaylistsRepository.kt

@@ -119,9 +119,9 @@ class PlaylistsRepository @Inject constructor(
             throw e
         }
         playlistDao.upsertAll(listOf(wire.toPlaylistEntity()))
-        playlistTrackDao.deleteByPlaylist(id)
-        playlistTrackDao.upsertAll(
-            wire.tracks.mapNotNull { row ->
+        playlistTrackDao.replacePlaylistTracks(
+            playlistId = id,
+            rows = wire.tracks.mapNotNull { row ->
                 row.trackId?.let { trackId ->
                     CachedPlaylistTrackEntity(
                         playlistId = id,

ci-requirements.md

@@ -9,11 +9,17 @@ Minstrel's four workflows consume two CI images:
 
 ```
 git.fabledsword.com/bvandeusen/ci-go:1.26
-git.fabledsword.com/bvandeusen/ci-flutter:3.44
+git.fabledsword.com/bvandeusen/ci-android:36
 ```
 
-- `ci-go:1.26` — Go server tests (`.gitea/workflows/test-go.yml`), web SPA tests (`.gitea/workflows/test-web.yml`), and the release container build (`.gitea/workflows/release.yml`).
-- `ci-flutter:3.44` — Flutter client tests + debug/release APK builds (`.gitea/workflows/flutter.yml`).
+- `ci-go:1.26` — Go server tests (`.gitea/workflows/test-go.yml`), web SPA tests (`.gitea/workflows/test-web.yml`), and the release container build (`release.yml`'s `image-release` job).
+- `ci-android:36` — native Kotlin/Compose client: ktlint + detekt + unit tests + debug APK (`.gitea/workflows/android.yml`), and the signed release APK (`release.yml`'s `android-release` job).
+
+**`ci-flutter` is no longer consumed.** The M8 rewrite replaced the Flutter
+client with the native Android app and `flutter.yml` was removed; `ci-android`
+took its place. `flutter_client/` is still in the tree but nothing builds it.
+CI-Runner still publishes `ci-flutter` and will retire it once that directory
+goes — so if the Flutter client is ever revived, say so there first.
 
 ## Image deps used
 
@@ -25,13 +31,20 @@ git.fabledsword.com/bvandeusen/ci-flutter:3.44
 - **docker buildx** — release container build + push in `release.yml`.
 - **curl** — release-asset polling / upload in `release.yml`.
 
-### From `ci-flutter:3.44`
-- **Flutter** (3.44 stable channel) — `flutter pub get`, `flutter analyze --fatal-infos`, `flutter test`, `flutter build apk` (debug + signed release).
-- **Dart** — `dart run tool/gen_tokens.dart`, `dart run build_runner build` (drift codegen).
-- **Android SDK + NDK + cmdline-tools + build-tools** — APK assembly + signing.
-- **Java 25** — Gradle / Android build.
+### From `ci-android:36`
+- **JDK 25** — Gradle launcher + Android build. Requires Gradle 9.1.0+ in
+  `android/gradle/wrapper`; older Gradle rejects JDK 25 with an opaque `"25.0.3"`
+  error. The workflows also set `JAVA_TOOL_OPTIONS=--enable-native-access=ALL-UNNAMED`
+  to silence Gradle's launcher-JVM restricted-method warning.
+- **Android SDK + cmdline-tools + build-tools 36.0.0** — APK assembly + signing.
+  No NDK: the native client has no C/C++ sources (this is why it isn't on
+  `ci-flutter`).
+- **ktlint + detekt** — `./gradlew ktlintCheck` and `./gradlew detekt` in
+  `android.yml`. Image pins track `android/gradle/libs.versions.toml` so local
+  and CI checks agree.
 - **git** — `actions/checkout@v4` baseline (and any shell git operations).
-- **base64 + curl** — keystore decode + release-asset upload in the tag-build path.
+- **base64 + curl** — keystore decode + release-asset upload in `release.yml`'s
+  `android-release` job.
 
 ## Per-job tool installs
 
@@ -39,10 +52,10 @@ None.
 
 ## Notes
 
-- **Label/image split.** Workflows keep `runs-on: go-ci` / `runs-on: flutter-ci` as the scheduling label per the [`ci-runners.md`](https://…/FabledRulebook/ci-runners.md) "label = scheduling handle, image = `container.image`" pattern. The labels are intentional handles, not toolchain assertions.
+- **Label/image split.** Workflows keep `runs-on: go-ci` / `runs-on: flutter-ci` as the scheduling label per the [`ci-runners.md`](https://…/FabledRulebook/ci-runners.md) "label = scheduling handle, image = `container.image`" pattern. The labels are intentional handles, not toolchain assertions — which is why the Android jobs still schedule on `flutter-ci` while pulling `ci-android:36`. Switch them to `android-ci` if that runner label is ever registered; nothing breaks either way.
 - **Integration-job docker-socket dependency.** `test-go.yml`'s integration job uses the runner's shared docker socket (`/var/run/docker.sock`) to bridge-IP-discover the per-job Postgres service container by name + network intersection — the dev compose's `minstrel-postgres-*` containers are explicitly skipped as belt-and-suspenders. Depends on `act_runner.valid_volumes` whitelisting the socket; if that ever stops auto-mounting, integration tests fail at the `docker inspect` step.
 - **Go toolchain pin.** `go.mod` is on `go 1.25.0` because `golang.org/x/crypto v0.51.0` declares 1.25 as its minimum. `ci-go:1.26` satisfies this with headroom. Future `x/crypto` bumps that move the Go floor should be paired with an image-tag bump in this file + the workflows.
-- **In-app update channel polling.** `release.yml` polls Gitea's release-asset API for up to 15 min on tag pushes to fetch the APK that `flutter.yml` is concurrently attaching to the same release. The asset eventually appears because `flutter.yml` and `release.yml` run in parallel on the same tag; if the polling times out, the server image ships without the bundled update channel (graceful degradation, not a build failure).
+- **In-app update channel — `needs:`, not polling.** `release.yml`'s `image-release` job declares `needs: [android-release]`, so on tag pushes the signed APK is guaranteed present before the image build starts — no polling window, no race. (The old cross-workflow polling against `flutter.yml` is gone with that workflow.) On non-tag `main` pushes `android-release` is skipped and `image-release` instead pulls the most recent release's APK and reconstructs its exact `versionName`, so `:latest` never ships without an update channel. It degrades to an empty `client/` — never a wrong version — if no release, asset, or tag commit-count can be resolved.
 - **Cache server reachability.** `test-web.yml` does NOT use `cache: 'npm'` on `actions/setup-node` — the Gitea Actions cache server isn't reachable from this runner's container network and `setup-node` was burning ~4m41s on ETIMEDOUT before failing open. With the migration to `ci-go:1.26`, `setup-node` is removed entirely (Node is in the image). The cache concern reappears if a future change re-introduces a network-dependent action.
 - **Artifacts — use the mirrored actions, never `actions/{upload,download}-artifact`.**
   ```yaml