Resolve a C018 runtime-expression against a fired event. Supports {$event.id}, {$event.<key>}, and a
JSON-Pointer tail {$event.body#/customer} / {$event.body#/data/object/customer}. Returns the stringified
value, or undefined when it doesn't resolve. Pure; never throws (an unresolvable expression is undefined, not an error).
Resolve a C018 runtime-expression against a fired event. Supports
{$event.id},{$event.<key>}, and a JSON-Pointer tail{$event.body#/customer}/{$event.body#/data/object/customer}. Returns the stringified value, or undefined when it doesn't resolve. Pure; never throws (an unresolvable expression is undefined, not an error).