docs(iroh-net): Update toplevel module documentation #8437

Job	Run time
Build wasm32	29s
Checking docs	1m 30s
Checking fmt	10s
Cross Build Only (armv7-linux-androideabi)	1m 0s
check_semver	4m 30s
Cross Build Only (aarch64-linux-android)	59s
Cross Test (i686-unknown-linux-gnu)	4m 11s
Cross Build Only (x86_64-unknown-freebsd)	1m 6s
Cross Build Only (x86_64-unknown-netbsd)	1m 8s
cargo deny	35s
clippy_check	3m 9s
Run network simulations/benchmarks	7m 22s
Minimal Supported Rust Version	1m 40s
CI Test Suite / Tests (ubuntu-latest, stable, all)	3m 21s
CI Test Suite / Tests (ubuntu-latest, stable, none)	2m 56s
CI Test Suite / Tests (ubuntu-latest, stable, default)	3m 0s
CI Test Suite / Tests (windows-latest, stable, all, x86_64-pc-windows-msvc)	3m 45s
CI Test Suite / Tests (macOS-arm-latest, stable, all)	3m 38s
CI Test Suite / Tests (windows-latest, stable, none, x86_64-pc-windows-msvc)	3m 47s
CI Test Suite / Tests (macOS-arm-latest, stable, none)	3m 30s
CI Test Suite / Tests (windows-latest, stable, default, x86_64-pc-windows-msvc)	3m 44s
CI Test Suite / Tests (macOS-arm-latest, stable, default)	3m 36s
	59m 6s

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