feat(cache): seed Reads and Bookmarks screens from cache on compose

Both screens now show cached data instantly on navigation instead of
showing loading states while re-fetching from relays.

- BookmarksScreen: reads cached BookmarkListEvent from addressableNotes,
  seeds public bookmark events from notes cache
- ReadsScreen: seeds long-form notes (kind 30023) from notes cache

Relay subscriptions still run to fetch fresh data in parallel.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

desktopApp/src/jvmMain/kotlin/com/vitorpamplona/amethyst/desktop/ui/BookmarksScreen.kt

@@ -121,6 +121,27 @@ fun BookmarksScreen(
         }
     }
 
+    // Seed from cache — bookmark list event may already be in addressableNotes
+    LaunchedEffect(account.pubKeyHex) {
+        val address = BookmarkListEvent.createBookmarkAddress(account.pubKeyHex)
+        val cachedNote = localCache.getOrCreateAddressableNote(address)
+        val cachedEvent = cachedNote.event as? BookmarkListEvent
+        if (cachedEvent != null) {
+            bookmarkList = cachedEvent
+            publicBookmarkIds =
+                cachedEvent
+                    .publicBookmarks()
+                    .filterIsInstance<EventBookmark>()
+                    .map { it.eventId }
+            // Seed public events from cache
+            publicBookmarkIds.forEach { id ->
+                val note = localCache.getNoteIfExists(id)
+                val event = note?.event
+                if (event != null) publicEventState.addItem(event)
+            }
+        }
+    }
+
     // Subscribe to user's bookmark list (kind 30001)
     rememberSubscription(connectedRelays, account.pubKeyHex, relayManager = relayManager) {
         if (connectedRelays.isNotEmpty()) {

desktopApp/src/jvmMain/kotlin/com/vitorpamplona/amethyst/desktop/ui/ReadsScreen.kt

@@ -46,6 +46,7 @@ import androidx.compose.material3.IconButton
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.collectAsState
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
@@ -207,6 +208,18 @@ fun ReadsScreen(
     var eoseReceivedCount by remember { mutableStateOf(0) }
     val initialLoadComplete = eoseReceivedCount > 0
 
+    // Seed from cache — long-form notes already consumed are in cache
+    LaunchedEffect(Unit) {
+        val cached =
+            localCache.notes.filterIntoSet { _, note ->
+                note.event is LongTextNoteEvent
+            }
+        cached.forEach { note ->
+            (note.event as? LongTextNoteEvent)?.let { eventState.addItem(it) }
+        }
+        if (cached.isNotEmpty()) eoseReceivedCount++
+    }
+
     // Load followed users for Following feed mode
     rememberSubscription(connectedRelays, account, feedMode, relayManager = relayManager) {
         val connectedRelays = connectedRelays