Smart indent rule for delegate grammar with alias

[sharwell]

1. Press Enter before the =.
2. Press Enter after the =.

lexer grammar TestLexer;

import
    ImportedS=S;

❓ For each of the two described cases, what should the indentation be, and why?

📝 For reference, currently the code assumes a delegate grammar will always fit on a single line (i.e. the alias, =, and delegate grammar name will appear on the same line).