Async Errors (RS101)

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Enforcement: rsc lint (rs edition only).

RS101: Unbounded async function

error[RS101]: async functions must have a deadline in rs edition
  help: add a deadline: async(Duration::from_millis(100)) fn unbounded()
  help: or opt out: #[allow(rs::unbounded_async)]

In edition = "rs", every async function must have an explicit deadline. An async function without a deadline can block indefinitely — a liveness failure in OS kernels and consensus nodes.

Inside cell! macro: use async(Duration) fn syntax. Outside cells: use #[bounded_async(Duration)] attribute macro.

Fix

// Inside cell!:
pub async(Duration::from_millis(100)) fn fetch(&self) -> Result<Data> {
    // ...
}

// Outside cell!:
#[bounded_async(Duration::from_millis(100))]
async fn fetch() -> Result<Data, AppError> {
    // ...
}

// Explicit opt-out (must justify):
#[allow(rs::unbounded_async)]
async fn special_case() -> Result<()> {
    // ...
}