fix(pins)_: delete pins when the og message is deleted (#6173)

Found when fixing https://github.com/status-im/status-desktop/issues/16639

When a message is deleted, we need to delete the pins too as they are no longer available. This was done using an ON DELETE clause (thanks @osmaczko)
I also made sure the SELECT query for the pins doesn't return deleted messages

protocol/message_persistence.go

@@ -1250,6 +1250,7 @@ func (db sqlitePersistence) PinnedMessageByChatIDs(chatIDs []string, currCursor
  			WHERE
  				pm.pinned = 1
  				AND NOT(m1.hide) AND m1.local_chat_id IN %s %s
+				AND m1.deleted = 0
  			ORDER BY cursor DESC
  			%s
  		`, allFields, cursorField, "(?"+strings.Repeat(",?", len(chatIDs)-1)+")", cursorWhere, limitStr),

protocol/migrations/sqlite/1733428521_pinned_messages_add_on_delete_clause.up.sql

@@ -0,0 +1,19 @@
+CREATE TABLE pin_messages_new (
+  id VARCHAR PRIMARY KEY NOT NULL,
+  message_id VARCHAR NOT NULL,
+  whisper_timestamp INTEGER NOT NULL,
+  chat_id VARCHAR NOT NULL,
+  local_chat_id VARCHAR NOT NULL,
+  clock_value INT NOT NULL,
+  pinned BOOLEAN NOT NULL,
+  pinned_by TEXT,
+  FOREIGN KEY (message_id) REFERENCES user_messages(id) ON DELETE CASCADE
+);
+
+INSERT INTO pin_messages_new (id, message_id, whisper_timestamp, chat_id, local_chat_id, clock_value, pinned, pinned_by)
+SELECT id, message_id, whisper_timestamp, chat_id, local_chat_id, clock_value, pinned, pinned_by
+FROM pin_messages;
+
+DROP TABLE pin_messages;
+
+ALTER TABLE pin_messages_new RENAME TO pin_messages;

protocol/persistence_test.go

@@ -666,6 +666,50 @@ func TestDeleteMessagesByChatID(t *testing.T) {
 
 }
 
+func TestDeletePinnedMessageByID(t *testing.T) {
+	db, err := openTestDB()
+	require.NoError(t, err)
+	p := newSQLitePersistence(db)
+	id := "1"
+
+	err = insertMinimalMessage(p, id)
+	require.NoError(t, err)
+
+	m, err := p.MessageByID(id)
+	require.NoError(t, err)
+	require.Equal(t, id, m.ID)
+
+	pinMessageProto := protobuf.PinMessage{
+		ChatId:      testPublicChatID,
+		MessageId:   m.ID,
+		Pinned:      true,
+		Clock:       2,
+		MessageType: protobuf.MessageType_PUBLIC_GROUP,
+	}
+
+	pinMessage := &common.PinMessage{
+		PinMessage: &pinMessageProto,
+	}
+
+	inserted, err := p.SavePinMessage(pinMessage)
+	require.NoError(t, err)
+	require.True(t, inserted)
+
+	pinnedMsgs, _, err := p.PinnedMessageByChatID(testPublicChatID, "", 10)
+	require.NoError(t, err)
+	require.Len(t, pinnedMsgs, 1)
+
+	err = p.DeleteMessage(m.ID)
+	require.NoError(t, err)
+
+	_, err = p.MessageByID(id)
+	require.EqualError(t, err, "record not found")
+
+	pinnedMsgs, _, err = p.PinnedMessageByChatID(testPublicChatID, "", 10)
+	require.NoError(t, err)
+	require.Len(t, pinnedMsgs, 0)
+}
+
 func TestMarkMessageSeen(t *testing.T) {
 	chatID := "test-chat"
 	db, err := openTestDB()