JVM properties suggestion

[dos65]

We choose to set Xmx512m by default in metals-vscode in scalameta/metals-vscode#603 .
However, in case if it would be enough for a particular project it would be nice to somehow inform the user that it's needed to change this setting.

A first step here might be adding improvements in handling server crashes. For example, Metals doesn't start with Xmx52m and produces the following message without any logs:

The Metals server crashed 5 times in the last 3 minutes. The server will not be restarted.

Also, @olafurpg mentioned that that we might perform JVM stats checks at runtime and notify user how to increase max memory setting : scalameta/metals-vscode#603 (comment)

Search terms:
jvm vscode xmx