Function vm_outcome_observed 

pub fn vm_outcome_observed(source: &str) -> RunOutcome

Run source on the bytecode VM in the OBSERVED profile (Wave 13): the VM emits the same observation events (Note/Warn/Record/During) the tree-walker does, into the observe channel — program output is byte- identical to vm_outcome. Pair with observe::install()/drain() to capture the emitted event stream.