The half of the #177 fallout #180's follow-up could not reach: WP20 wrapped
the session bin's single-threaded-startup env writes in the `unsafe {}`
blocks edition 2024 requires — under `#![forbid(unsafe_code)]`, which no
inner attribute can override, so `punktfunk-client-session` fails with two
hard errors on every Windows leg (main push runs 17615/17616 red at Build;
verified on .173). Same resolution as #180 gave the GTK shell: `forbid`
becomes `deny`, and the three documented SAFETY sites carry the localized
`#[allow(unsafe_code)]` pf-update models.