Function compile_program_traced 

pub fn compile_program_traced(
    source: &str,
) -> Result<(CompileOutput, FiredOptimizations), ParseError>

Compile source while recording which optimizations actually FIRED — the honest, single-compile alternative to optimizations_used’s O(N) diff. An optimization is “fired” when it actually changed the program or emitted its optimized form for this compile, under the effective (normalized) config. Reusable: any caller can compile a program and learn what fired, for tracing and tooling.