d2ef53b090
cargo fmt --check (CI gate per AGENTS.md) flagged import-ordering + line-wrapping drift across slice-2's committed code (rutster-tap-echo, rutster-tap, rutster binary tap_engine + routes) and the slice-1-review -fixes rebase (loop_driver, rtc_session, session_map). Purely cosmetic: alphabetical use ordering, line wrapping under 100 cols. No semantic changes.