Toolchain drift (clippy 0.1.97): pre-existing on main, all mechanical
and behaviour-preserving.
- bread-theme/gtk.rs: `type AppCssBuilder` alias for the repeated
`Rc<dyn Fn(&Palette) -> String>` (type_complexity ×4).
- bread-theme/lib.rs: `sort_by_key(|..| Reverse(len))` (unnecessary_sort_by).
- bread-theme/output.rs: `io::Error::other`; struct-init in a test.
- bread-utils/singleton.rs: explicit `.truncate(false)` on the lock file
open — we only clear it after winning the lock (suspicious_open_options).
- bread-polkit/identity.rs: elide `pick_user` lifetimes.
Adds `bread-theme layerrules`, which writes the active shell theme's
[compositor] table to ~/.config/hypr/layerrules.json (atomic write). This
lets ~/.config/hypr/scripts/ui/rules.lua read theme-driven blur/transparency/
animation for the breadbar/breadbox layer-shell namespaces instead of having
them hardcoded, following THEME_SYSTEM_PLAN.md §9. rules.lua keeps its
previous hardcoded rules as a pcall-guarded fallback for when the JSON is
missing or malformed (lives outside this repo, so not part of this commit).
Also fixes a pre-existing test race: shell::tests and the new
layerrules::tests both mutate XDG_CONFIG_HOME in parallel `cargo test`
threads but previously used separate, unrelated locks (or none), so they
could observe each other's env var changes mid-test. Both now share
bread_theme::test_support::XDG_CONFIG_HOME_LOCK.
Each Hyprland/GDK connector can have its own palette and stylesheet
under $XDG_RUNTIME_DIR/bread/{palettes,themes}/. GTK apps bind a
widget-level provider so two windows in one process can follow
different wallpapers. Bump workspace version to 0.7.4 for the tag.
