Indentation defines the scope

[JoanGi]

💣 Describe the issue or problem you detected

To define more closely the scope, and therefore be able to provide more accurate suggestion during the autocompletion of the language, it will be useful that indentation level defines the scope, as similar as python does.

📋 Provide the solution you'd like

In this issue, there is a proposed path to achieve this behavior.

eclipse-langium/langium#782