Code review:

- @Volatile ScheduledPostNotifier.channel: two workers firing in the
  same window can race on ensureChannel from different IO threads.
  createNotificationChannel is idempotent, but the field write needs a
  visibility fence so both threads see the cached reference.
- @Volatile PoolEventOutbox.eventOutbox map ref + PoolEventOutboxState
  .relaysRemaining set ref. The new pendingPublishRelaysFor polling
  path reads these from the WorkManager IO thread; mutations still
  happen on NostrClient's IO scope. Pre-existing visibility gap that
  this poll surface exposed; @Volatile is the minimal fix.
- ScheduledPostsScreen.SectionLabel: read the locale from
  LocalConfiguration.current.locales[0] (the Compose-resolved locale)
  rather than Locale.getDefault() (the system locale, which can drift
  from app config and breaks Turkish I/i casing).

quartz/src/commonMain/kotlin/com/vitorpamplona/quartz/nip01Core/relay/client/pool/PoolEventOutbox.kt

@@ -31,6 +31,11 @@ import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.update
 
 class PoolEventOutbox {
+    // @Volatile so the polling path (INostrClient.pendingPublishRelaysFor)
+    // sees current state from threads that didn't write the map. Mutations
+    // still happen on NostrClient's IO scope; this only closes the
+    // visibility gap for cross-thread readers.
+    @Volatile
     private var eventOutbox = mapOf<HexKey, PoolEventOutboxState>()
     val relays = MutableStateFlow(setOf<NormalizedRelayUrl>())
 

quartz/src/commonMain/kotlin/com/vitorpamplona/quartz/nip01Core/relay/client/pool/PoolEventOutboxState.kt

@@ -26,7 +26,7 @@ import com.vitorpamplona.quartz.utils.TimeUtils
 
 class PoolEventOutboxState(
     val event: Event,
-    var relaysRemaining: Set<NormalizedRelayUrl>,
+    @Volatile var relaysRemaining: Set<NormalizedRelayUrl>,
 ) {
     private var failures = mapOf<NormalizedRelayUrl, Tries>()