Flashing text when re-sharing battle

[Paul-Ladyman]

When a battle is shared a placeholder '. . .' is shown before the player session link is displayed. This is mainly done to cover the time required to communicate with AWS AppSync.

However the placeholder is also shown until the the player session link has been copied to the clipboard. If the DM stops sharing the battle and then starts sharing again, we do not trigger the call to AppSync again. This means on the second share the placeholder is only shown whilst the link is copied, which is very quick and gives the effect of the link blinking or flashing on the screen when it is displayed.