Summary

• include bind, listen, and shutdown ops test modules in the ops integration suite
• adapt those tests to use the shared nested ops common module
• update socket setup to use current Resource-returning helpers and avoid fixed ports in concurrent bind coverage

Test Plan

• cargo fmt -p lio
• cargo test -p lio --test ops bind -- --nocapture
• cargo test -p lio --test ops listen -- --nocapture
• cargo test -p lio --test ops shutdown -- --nocapture
• cargo test -p lio --test ops