fix: Don't make message OutDelivered after successful resending to new broadcast member

Follow-up to 970222f. We shouldn't update the message state to `OutDelivered` if message sending
failed before and the message was re-sent successfully only to a new broadcast member.

src/message.rs

@@ -140,8 +140,20 @@ SELECT ?1, rfc724_mid, pre_rfc724_mid, timestamp, ?, ? FROM msgs WHERE id=?1
         Ok(())
     }
 
-    pub(crate) async fn set_delivered(self, context: &Context) -> Result<()> {
-        update_msg_state(context, self, MessageState::OutDelivered).await?;
+    /// Returns whether the message state is updated to `OutDelivered`.
+    pub(crate) async fn set_delivered(self, context: &Context) -> Result<bool> {
+        if context
+            .sql
+            .execute(
+                // Only update `OutPending` i.e. if the message is (re-)sent to all chat members.
+                "UPDATE msgs SET state=?, error='' WHERE id=? AND state=?",
+                (MessageState::OutDelivered, self, MessageState::OutPending),
+            )
+            .await?
+            == 0
+        {
+            return Ok(false);
+        }
         let chat_id: Option<ChatId> = context
             .sql
             .query_get_value("SELECT chat_id FROM msgs WHERE id=?", (self,))
@@ -153,7 +165,7 @@ SELECT ?1, rfc724_mid, pre_rfc724_mid, timestamp, ?, ? FROM msgs WHERE id=?1
         if let Some(chat_id) = chat_id {
             chatlist_events::emit_chatlist_item_changed(context, chat_id);
         }
-        Ok(())
+        Ok(true)
     }
 
     /// Bad evil escape hatch.
@@ -1414,6 +1426,9 @@ pub enum MessageState {
     /// The user has pressed the "send" button but the message is not
     /// yet sent and is pending in some way. Maybe we're offline (no
     /// checkmark).
+    ///
+    /// This state means that the message is being (re-)sent to all chat members. It shalln't be
+    /// used e.g. for resending only to a new broadcast member.
     OutPending = 20,
 
     /// *Unrecoverable* error (*recoverable* errors result in pending