Show indicator when somebody is typing into Add Action field

[davidje13]

In a distributed retro, it is not obvious when somebody is entering an action; this can lead to multiple participants adding the same action, or actions being missed.

When entering text into the Add Action field, other users should see an indicator. When the action is posted, this indicator should disappear. It may be desirable to show if multiple people are entering actions.

This represents the first piece of "per user" state, so it is not obvious how it should be handled in the API. Also it is important that any text entered this way is secure (i.e. encrypted), so using the general retro state is not ideal. One possibility would be to use items with a new type. The ownership of these items may be tricky to track, and they will need to expire after some period of inactivity to ensure lost connections do not lead to a permanently visible indicator.

Possible UI options:

• a symbol / animation to indicate somebody is typing
• the text which is being typed appearing close to the field (e.g. to the side) - could show multiple (perhaps limited to earliest if too many)
• text stating how many people are typing

When an action item is added, it may be desirable to briefly display it on viewers' screens (sticky) - perhaps toast-style.