Smooth scrolling, dark reader, mark-read-on-scroll, feed names, per-feed reader-mode opt-out

- ReaderScreen: AndroidView's update() was reloading the WebView's HTML on
  every recomposition (e.g. isSaving flipping mid-read), resetting scroll
  position -- this is what made scrolling feel unsmooth. Now only reloads
  when the content string actually changes.
- ReaderScreen: reader content now uses a hardcoded dark palette instead of
  browser-default white, matching the app's always-dark theme.
- ArticleListScreen: mark-as-read-on-scroll -- once an article has scrolled
  fully above the viewport it's marked read, the standard feed-reader
  behavior, via a new batched ArticleDao.markReadBatch(). Verified against
  the on-device DB (scrolled-past articles flipped to isRead=1, the
  still-visible one stayed unread).
- ArticleListItem/queries: LEFT JOIN feeds for a feedTitle column, shown per
  row in the Unread/Saved aggregated views and as a reader subtitle; the
  per-feed article list's top bar now shows the real feed title instead of
  a generic "Articles".
- FeedEntity.readerModeDisabled (schema v3, migration 2->3): per-feed
  opt-out of the Readability fallback/toggle, toggled from a new icon in
  FeedListScreen. Added for kottke.org specifically -- confirmed its thin
  linkblog posts were making Readability extract the page footer instead
  of the actual post; disabling reader mode for that feed now shows its
  own (short but correct) content instead.

All verified live on the emulator against the real 107-feed dataset.

3 files changed, 26 insertions, 8 deletions

diff --git a/app/src/main/java/org/terst/feedreader/data/AppDatabase.kt b/app/src/main/java/org/terst/feedreader/data/AppDatabase.kt
index e2f6c1a..4cf0ecd 100644
--- a/app/src/main/java/org/terst/feedreader/data/AppDatabase.kt
+++ b/app/src/main/java/org/terst/feedreader/data/AppDatabase.kt
@@ -9,7 +9,7 @@ import androidx.room.migration.Migration
 
 @Database(
     entities = [FeedEntity::class, ArticleEntity::class, FilterRuleEntity::class],
-    version = 2,
+    version = 3,
     exportSchema = false
 )
 abstract class AppDatabase : RoomDatabase() {
@@ -31,12 +31,19 @@ abstract class AppDatabase : RoomDatabase() {
             }
         }
 
+        // v3: added FeedEntity.readerModeDisabled (per-feed reader-mode opt-out).
+        private val MIGRATION_2_3 = object : Migration(2, 3) {
+            override fun migrate(db: SupportSQLiteDatabase) {
+                db.execSQL("ALTER TABLE feeds ADD COLUMN readerModeDisabled INTEGER NOT NULL DEFAULT 0")
+            }
+        }
+
         fun get(context: Context): AppDatabase = instance ?: synchronized(this) {
             instance ?: Room.databaseBuilder(
                 context.applicationContext,
                 AppDatabase::class.java,
                 "feedreader.db"
-            ).addMigrations(MIGRATION_1_2).build().also { instance = it }
+            ).addMigrations(MIGRATION_1_2, MIGRATION_2_3).build().also { instance = it }
         }
     }
 }
diff --git a/app/src/main/java/org/terst/feedreader/data/Daos.kt b/app/src/main/java/org/terst/feedreader/data/Daos.kt
index f80cce3..8fe2ec2 100644
--- a/app/src/main/java/org/terst/feedreader/data/Daos.kt
+++ b/app/src/main/java/org/terst/feedreader/data/Daos.kt
@@ -48,25 +48,30 @@ data class ArticleListItem(
     val isRead: Boolean,
     val isSaved: Boolean,
     val stashArtifactId: String?,
-    val createdAt: Long
+    val createdAt: Long,
+    val feedTitle: String?  // via LEFT JOIN feeds -- null for standalone share-sheet saves with no feedId
 ) : Titled
 
 private const val ARTICLE_LIST_COLUMNS =
-    "id, feedId, title, link, author, publishedAt, imageUrl, isRead, isSaved, stashArtifactId, createdAt"
+    "articles.id, articles.feedId, articles.title, articles.link, articles.author, articles.publishedAt, " +
+        "articles.imageUrl, articles.isRead, articles.isSaved, articles.stashArtifactId, articles.createdAt, " +
+        "feeds.title AS feedTitle"
+
+private const val ARTICLE_LIST_FROM = "articles LEFT JOIN feeds ON articles.feedId = feeds.id"
 
 @Dao
 interface ArticleDao {
     // Unread-first, newest-first -- the default "what's new" view across every feed.
-    @Query("SELECT $ARTICLE_LIST_COLUMNS FROM articles WHERE isRead = 0 ORDER BY publishedAt DESC")
+    @Query("SELECT $ARTICLE_LIST_COLUMNS FROM $ARTICLE_LIST_FROM WHERE articles.isRead = 0 ORDER BY articles.publishedAt DESC")
     fun observeUnread(): Flow<List<ArticleListItem>>
 
     @Query("SELECT feedId, COUNT(*) as count FROM articles WHERE isRead = 0 AND feedId IS NOT NULL GROUP BY feedId")
     fun observeUnreadCounts(): Flow<List<FeedUnreadCount>>
 
-    @Query("SELECT $ARTICLE_LIST_COLUMNS FROM articles WHERE feedId = :feedId ORDER BY publishedAt DESC")
+    @Query("SELECT $ARTICLE_LIST_COLUMNS FROM $ARTICLE_LIST_FROM WHERE articles.feedId = :feedId ORDER BY articles.publishedAt DESC")
     fun observeByFeed(feedId: String): Flow<List<ArticleListItem>>
 
-    @Query("SELECT $ARTICLE_LIST_COLUMNS FROM articles WHERE isSaved = 1 ORDER BY createdAt DESC")
+    @Query("SELECT $ARTICLE_LIST_COLUMNS FROM $ARTICLE_LIST_FROM WHERE articles.isSaved = 1 ORDER BY articles.createdAt DESC")
     fun observeSaved(): Flow<List<ArticleListItem>>
 
     @Query("SELECT * FROM articles WHERE id = :id")
@@ -84,6 +89,11 @@ interface ArticleDao {
     @Query("UPDATE articles SET isRead = :read WHERE id = :id")
     suspend fun setRead(id: String, read: Boolean)
 
+    // Used for mark-as-read-on-scroll in the article list -- batched per scroll-settle
+    // rather than one query per row.
+    @Query("UPDATE articles SET isRead = 1 WHERE id IN (:ids)")
+    suspend fun markReadBatch(ids: List<String>)
+
     @Query("UPDATE articles SET isRead = 1 WHERE feedId = :feedId")
     suspend fun markAllReadForFeed(feedId: String)
 
diff --git a/app/src/main/java/org/terst/feedreader/data/Entities.kt b/app/src/main/java/org/terst/feedreader/data/Entities.kt
index 29d4fe4..f943f78 100644
--- a/app/src/main/java/org/terst/feedreader/data/Entities.kt
+++ b/app/src/main/java/org/terst/feedreader/data/Entities.kt
@@ -12,7 +12,8 @@ data class FeedEntity(
     val lastFetchedAt: Long? = null,
     val etag: String? = null,            // conditional-GET caching (If-None-Match) to avoid re-downloading unchanged feeds
     val lastModified: String? = null,    // conditional-GET caching (If-Modified-Since)
-    val lastError: String? = null        // set when a fetch fails; cleared on the next successful fetch
+    val lastError: String? = null,       // set when a fetch fails; cleared on the next successful fetch
+    val readerModeDisabled: Boolean = false // per-feed opt-out: never auto/manually switch to Readability for this feed's articles (e.g. a feed whose own formatting is better than what extraction produces)
 )
 
 @Entity(tableName = "articles")