Function attempt_access 

async fn attempt_access(
    client: &PasswordManagerClient,
    send_id: &str,
    access_key: &SendAccessKey,
    inputs: &ReceiveInputs,
) -> Result<SendAccessTokenResponse>

Negotiate a send-access token, prompting for whatever credential the server says the Send needs. Mirrors the legacy attemptAccess: ask with no credentials first and branch on the typed send_access_error_type the server returns.

Legacy wraps every token request in a 3-attempt retry loop (getTokenWithRetry) for a {kind: "expired"} case tied to its persistent send-access-token cache, itself keyed on sendId alone with no host component — part of what PM-40120 tracks. This port’s own cache (send_access_token_cache) is keyed on (resolved_host, send_id) instead, and evicts rather than retries on a rejected cached token (see run_receive), so there’s no multi-attempt loop to replicate here.