fn new(model: impl Into<String>) -> Self

fn with_limits(model: impl Into<String>, max_tokens: usize, output_reserve: usize) -> Self

fn available(&self) -> usize

fn allocate(&self) -> BudgetAllocation

fn allocate_custom(
        &self,
        system_pct: f64,
        history_pct: f64,
        tools_pct: f64,
    ) -> BudgetAllocation