refactor(iroh): add `--start` option to CLI commands #5842

Job	Run time
Build and test (Windows) (windows-latest, nightly, x86_64-pc-windows-msvc)	12m 49s
Cross compile (i686-unknown-linux-gnu)	3m 4s
Build and test (Windows) (windows-latest, stable, x86_64-pc-windows-msvc)	12m 38s
Build and test (Nix) (ubuntu-latest, nightly)	9m 53s
Cross compile (armv7-linux-androideabi)	46s
Build and test (Nix) (ubuntu-latest, stable)	24m 22s
Cross compile (aarch64-linux-android)	37s
Build and test (Nix) (macOS-arm-latest, nightly)	13m 21s
Build and test (Nix) (macOS-arm-latest, stable)	13m 25s
Checking fmt and docs	3m 4s
clippy_check	2m 53s
Minimal Supported Rust Version	1m 54s
cargo deny	27s
Run network simulations/benchmarks	5m 13s
Build release binaries	0s
	1h 44m 26s

Provide feedback