fix: use configured localnet port in doctor command

[ygd58]

Fixes #40.

Replace hardcoded port 3040 with project.config.localnet.port in build_doctor_report().

// Before
rows.push(check_port_warn(
    "sequencer port 3040",
    "127.0.0.1:3040",
    ...
));

// After
let localnet_port = project.config.localnet.port;
let localnet_addr = format!("127.0.0.1:{localnet_port}");
rows.push(check_port_warn(
    &format!("sequencer port {localnet_port}"),
    &localnet_addr,
    ...
));

[weboko]

duplicate of #41