EbnfParser | ISO EBNF notation parser | Parser library

I've just started writing a simple parser in C# that you can find here: https://github.com/JohnnyErnest/LexerParser/blob/main/Program.cs#L1078

The main feature being that I wanted to be able to write a JSON configuration for some grammar that I want to analyze, load up the configuration at runtime and evaluate some string input via the lexer/parser and generate a tree with information about each node for things like syntax highlighting and extracting variables from sections of a parsed text, rather than using a third party tool like a yacc/bison clone to create code to be compiled from a grammar, for some languages like SQL/CSS/HTML.

The simple question is, what are some other good methods of detecting recursion problems early from malformed input before a StackOverflowException? The details are below.

I don't have grammars fully built out yet for various languages, just simple tests of some basic grammar so far, but I ran across a problem when trying to implement EBNF like: https://en.wikipedia.org/wiki/Extended_Backus%E2%80%93Naur_form when having to deal with how the right-hand side of grammar statements are evaluated like so: