PC Messages: Make text notifications more informative and link to mobile app if installed

Love the messaging in the PC and also the recent integration with the Mobile app.

A couple of improvements I would like to suggest are:

Text alerts be more informative.

Currently, it only provides a very generic message that there's a new message, along with a link to the case.

At the very least, provide the sender's name and the decedent's name.

Also, I think if we have the mobile app installed, it should open the case/message in the mobile app, rather than opening the browser, which requires login and it cumbersome to use on a mobile device.

Even better, make the app send a Push message containing the full text (or truncated) of the message.