Custodial routing. The router pulls input_amount of input_token
from user, runs each step on the held funds (using
authorize_as_current_contract to authorize what each target pulls
from the router), takes a single affiliate fee at fee_position, and
finally transfers the router's output_token balance to user.
fee_position semantics:
0 — fee is taken from input_token before any step
runs (basis: input_amount).i ∈ 1..=n — fee is taken from steps[i-1].output_token after
that step returns (basis: router's balance of that
token at that moment). steps[i-1].output_token MUST
be Some.InvalidFeePosition error.When the fee is taken on a step's output_token, returns[i-1] is
refreshed to the post-fee router balance so any later step's
arg_refs thread the actually available amount.
Returns: the user's final received amount of output_token.
fn route(
env: soroban_sdk::Env,
user: soroban_sdk::Address,
swap_id: soroban_sdk::BytesN<16>,
input_token: soroban_sdk::Address,
input_amount: u128,
output_token: soroban_sdk::Address,
steps: soroban_sdk::Vec,
affiliate_fees: soroban_sdk::Vec,
fee_position: u32,
) -> u128 Permissionless TTL keep-alive. Anyone can call to keep the contract's instance entry alive during cold periods.
fn bump_ttl(env: soroban_sdk::Env)