Function run_block_with_logger 

pub(crate) fn run_block_with_logger<F>(
    eval: &mut MilkEvaluator,
    block: &CompiledBlock,
    on_err: F,
)
where
    F: FnMut(usize, EvalError),

Run a CompiledBlock against eval, calling on_err(node_index, err) for each evalexpr-fallback node that fails. Centralises the “prefer bytecode (infallible) / log per-equation failures on the Nodes path” pattern shared by wave_phase, shape_phase and the per-frame eval in [MilkEngine::update].