Add WebChat version to UserAgent

[EricDahlvang]

Feature Request

It would be useful for diagnostics and analytics to know the WebChat version that is sending messages.

[Enhancement]

[compulim]

Great idea.

The window.WebChat.createDirectLine function in the bundle should put/append Web Chat version as bot agent. There is an option called botAgent.

@EricDahlvang few questions:

• What do you think about the format of the bot agent? E.g. WebChat/4.4.1?
• How about the user want to append their own? Should we always append WebChat/4.4.1 to what the user provided?
• Web Chat has different loading mechanisms, should we list them out?
  • Bundle: full bundle (include Adaptive Cards), minimal bundle (no Markdown)
  • Channel: CDN, NPM, embed (currently, it is difficult to get this)

@corinagum it's modifying the bundle, not difficult because it is more-or-less similar to how createStyleSet work. And you know we have 3 versions in meta tag, use the one from bundle.

[EricDahlvang]

The adaptive cards version can be determined based on the WebChat build version. But, as much information as we can provide regarding customer enabled features and loading mechanisms seems good.