msglist: Add star marker in messages

Author: sirpengi

lib/widgets/message_list.dart

@@ -847,7 +847,12 @@ class MessageWithPossibleSender extends StatelessWidget {
                     if ((message.reactions?.total ?? 0) > 0)
                       ReactionChipsList(messageId: message.id, reactions: message.reactions!)
                   ])),
-              const SizedBox(width: 16),
+              SizedBox(width: 16,
+                child: message.flags.contains(MessageFlag.starred)
+                  ? Icon(ZulipIcons.star,
+                      size: 16,
+                      color: const HSLColor.fromAHSL(0.5, 47, 1, 0.41).toColor())
+                  : const SizedBox.shrink()),
             ])),
         ],
       ));