Fix crash on blank-guid articles; simplify browser back; backlog notes

- FeedParser: a feed with a literal empty <guid>/<id> element (confirmed
  live: a Mother Jones entry) produced an ArticleEntity with id = "" --
  the fallback chain only checked for null, not blank, so an empty-but-
  present tag passed straight through. An empty-string primary key broke
  Navigation Compose's route matching and crashed on tap ("tapping this
  article crashes the app"). Fixed both RSS and Atom paths to treat blank
  the same as null before falling back to a link-based id. Schema v5
  migration deletes any row already on-device with the bad id; it'll
  come back with a real, hash-based id on the next fetch of that feed.
  Verified live: zero blank-id rows after the migration and a fresh
  fetch, no crash.

- BrowserScreen: back (both the system gesture and the in-app arrow) now
  always closes the screen directly, rather than stepping through
  in-page WebView history first. Reported live as not making sense for
  multi-page browsing (search results -> article -> another link, etc.)
  -- you'd have to tap back that many times just to leave. There's no
  separate in-page-back affordance now, matching how every other screen
  in this app behaves.

- Tried moving swipe-to-next-article detection off Compose's gesture
  system entirely (a passive native OnTouchListener on the WebView, never
  consuming) on the theory that Compose's gesture arbitration was the
  source of reported scroll jerkiness. Reverted after confirming live
  that swipe stopped working at all with that approach -- a worse
  regression than unproven jerkiness. Back to the known-working
  Compose-based detector; the jerkiness complaint itself is still open.

- BACKLOG.md: added bug-report-button, smaller-title-text, and
  bottom-action-strip-with-auto-hide notes.

2 files changed, 23 insertions, 4 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 441556b..66722fd 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 = 4,
+    version = 5,
     exportSchema = false
 )
 abstract class AppDatabase : RoomDatabase() {
@@ -77,12 +77,25 @@ abstract class AppDatabase : RoomDatabase() {
             }
         }
 
+        // v5: a feed with a literal empty <guid>/<id> element (confirmed live: a Mother
+        // Jones entry) produced an ArticleEntity with id = "" -- FeedParser fell back to
+        // itemLink only when the guid was null, not when it was blank. An empty-string
+        // primary key broke Navigation Compose's route matching and crashed on tap. The
+        // parser is fixed for future fetches; this cleans out any row already on-device
+        // with the bad id so it doesn't keep crashing. It'll come back with a real,
+        // hash-based id on the next fetch of that feed.
+        private val MIGRATION_4_5 = object : Migration(4, 5) {
+            override fun migrate(db: SupportSQLiteDatabase) {
+                db.execSQL("DELETE FROM articles WHERE trim(id) = ''")
+            }
+        }
+
         fun get(context: Context): AppDatabase = instance ?: synchronized(this) {
             instance ?: Room.databaseBuilder(
                 context.applicationContext,
                 AppDatabase::class.java,
                 "feedreader.db"
-            ).addMigrations(MIGRATION_1_2, MIGRATION_2_3, MIGRATION_3_4).build().also { instance = it }
+            ).addMigrations(MIGRATION_1_2, MIGRATION_2_3, MIGRATION_3_4, MIGRATION_4_5).build().also { instance = it }
         }
     }
 }
diff --git a/app/src/main/java/org/terst/feedreader/data/FeedParser.kt b/app/src/main/java/org/terst/feedreader/data/FeedParser.kt
index 629afe6..8b37e55 100644
--- a/app/src/main/java/org/terst/feedreader/data/FeedParser.kt
+++ b/app/src/main/java/org/terst/feedreader/data/FeedParser.kt
@@ -120,7 +120,12 @@ object FeedParser {
                         inItem = false
                         val content = itemContent ?: itemDescription
                         items += ParsedItem(
-                            guid = itemGuid ?: itemLink.ifBlank { null },
+                            // .ifBlank, not just ?: -- a feed with a literal empty <guid></guid>
+                            // (confirmed live: a Mother Jones entry) gives itemGuid = "" here,
+                            // which is non-null and so passed straight through a plain `?:`,
+                            // landing as the article's primary key. An empty-string id broke
+                            // Navigation Compose's route matching and crashed on tap.
+                            guid = itemGuid?.ifBlank { null } ?: itemLink.ifBlank { null },
                             title = itemTitle,
                             link = itemLink,
                             author = itemAuthor,
@@ -195,7 +200,8 @@ object FeedParser {
                         inEntry = false
                         val content = entryContent ?: entrySummary
                         items += ParsedItem(
-                            guid = entryId ?: entryLink.ifBlank { null },
+                            // Same blank-vs-null fix as the RSS path above.
+                            guid = entryId?.ifBlank { null } ?: entryLink.ifBlank { null },
                             title = entryTitle,
                             link = entryLink,
                             author = entryAuthor,