Description of changes:

Since Rust 1.77 std::net::SocketAddr and related types have been available in core::net. This means we no longer need to gate some of the conversion methods we had for converting between our own socket address representations and the net::SocketAddr types behind and std feature flag.

I've also added a From impl for LocalAddress and RemoteAddress, as that may be useful in #2906

Call-outs:

std::net::ToSocketAddrs remains in std so we can't remove the entire std_conversion mod

Testing:

Existing tests pass and ./scripts/test_no_std script passes

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