Fix Unread/startup crash; add reader-mode toggle and swipe navigation

- Root cause of the reported crashes: observeUnread/observeByFeed/
  observeSaved used SELECT *, pulling feedContentHtml/extractedContent
  (potentially large per-article blobs) just to render a list row.
  With 107 feeds worth of real articles this blows past Android's
  CursorWindow/memory limits, scaling with item count -- and since
  Unread is now the landing screen, it crashed at startup too. Added
  an ArticleListItem projection excluding the heavy content columns;
  list queries now only select what a row actually renders.
- FilterRuleEngine now takes a small Titled interface (title/feedId)
  instead of the full entity, so it works with both ArticleEntity and
  the new lighter projection.
- Reader-mode toggle: a button in the reader to manually switch
  between feed-provided content and Readability-extracted full text,
  matching Inoreader's full-text-view toggle (previously only an
  automatic fallback when feed content was thin).
- Swipe between articles: ReaderScreen now wraps a HorizontalPager over
  a snapshot of the current list's article-id order, so swiping moves
  to the next/previous article. Snapshotted rather than live, since
  marking an article read would otherwise drop it from the live Unread
  query mid-swipe and shift every later page underneath the user.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EZ7ikw2ukGJFTHE3bJS7zL

1 files changed, 29 insertions, 6 deletions

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 2240ff4..f80cce3 100644
--- a/app/src/main/java/org/terst/feedreader/data/Daos.kt
+++ b/app/src/main/java/org/terst/feedreader/data/Daos.kt
@@ -31,20 +31,43 @@ interface FeedDao {
 
 data class FeedUnreadCount(val feedId: String, val count: Int)
 
+// A projection excluding feedContentHtml/extractedContent -- the potentially
+// large per-article content blobs that list views (row title/date/thumbnail)
+// never need. Selecting them for every row of a big result set is what was
+// crashing the Unread view once real feed volume (107 feeds worth of
+// articles) hit it: Android's per-row/CursorWindow limits are sized for
+// "many small rows," not "many rows each carrying a full article's HTML."
+data class ArticleListItem(
+    val id: String,
+    override val feedId: String?,
+    override val title: String,
+    val link: String,
+    val author: String?,
+    val publishedAt: Long?,
+    val imageUrl: String?,
+    val isRead: Boolean,
+    val isSaved: Boolean,
+    val stashArtifactId: String?,
+    val createdAt: Long
+) : Titled
+
+private const val ARTICLE_LIST_COLUMNS =
+    "id, feedId, title, link, author, publishedAt, imageUrl, isRead, isSaved, stashArtifactId, createdAt"
+
 @Dao
 interface ArticleDao {
     // Unread-first, newest-first -- the default "what's new" view across every feed.
-    @Query("SELECT * FROM articles WHERE isRead = 0 ORDER BY publishedAt DESC")
-    fun observeUnread(): Flow<List<ArticleEntity>>
+    @Query("SELECT $ARTICLE_LIST_COLUMNS FROM articles WHERE isRead = 0 ORDER BY 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 * FROM articles WHERE feedId = :feedId ORDER BY publishedAt DESC")
-    fun observeByFeed(feedId: String): Flow<List<ArticleEntity>>
+    @Query("SELECT $ARTICLE_LIST_COLUMNS FROM articles WHERE feedId = :feedId ORDER BY publishedAt DESC")
+    fun observeByFeed(feedId: String): Flow<List<ArticleListItem>>
 
-    @Query("SELECT * FROM articles WHERE isSaved = 1 ORDER BY createdAt DESC")
-    fun observeSaved(): Flow<List<ArticleEntity>>
+    @Query("SELECT $ARTICLE_LIST_COLUMNS FROM articles WHERE isSaved = 1 ORDER BY createdAt DESC")
+    fun observeSaved(): Flow<List<ArticleListItem>>
 
     @Query("SELECT * FROM articles WHERE id = :id")
     suspend fun getById(id: String): ArticleEntity?