feat(ui-flow): emit mark-notification-read-cleared for desktop unread dismiss

After markRead, push mark-notification-read-cleared with guild and channel ids
so desktop can dismiss channel unread desktop notifications.

Co-authored-by: Cursor <[email protected]>

index.js

@@ -744,8 +744,15 @@ async function dispatchUiMessage (platform, msg, hooks = {}) {
     return true
   }
   if (t === 'mark-notification-read') {
-    await platform.notifications?.markRead(msg.notificationId)
+    const row = await platform.notifications?.markRead(msg.notificationId)
     pushState()
+    if (row?.channelId) {
+      send({
+        type: 'mark-notification-read-cleared',
+        guildId: row.guildId || platform.guild?.guild?.id || null,
+        channelId: row.channelId
+      })
+    }
     return true
   }
   if (t === 'open-notification') {