Polish Waybar and add Bluetooth and walker service

Refactor Waybar config and CSS: add rgb/radius helpers and tweak
sizes, spacing, colors, tooltips, icons and transitions

Enable gtk-layer-shell and reload-on-change. Move exec-once into
settings and adjust modules and workspaces formatting

Add blueman and bluez to basic apps for Bluetooth support

Add elephant to home packages and add a systemd user service for
walker; change Hyprland exec-once to enable and start elephant.service

docs/CONTRIBUTING.md

@@ -1,16 +1,16 @@
-# Contributing to Nixy
-
-Everybody is invited and welcome to contribute to Nixy. There is a lot to do... Check the issues!
-
-The process is straight-forward.
-
-- Read [How to get faster PR reviews](https://github.com/kubernetes/community/blob/master/contributors/guide/pull-requests.md#best-practices-for-faster-reviews) by Kubernetes (but skip step 0 and 1)
-- Fork Nixy [git repository](https://github.com/anotherhadi/nixy).
-- Write your changes (new theme, bug fixes, issues fix, ...).
-- Create a Pull Request against the main branch of Nixy.
-
-> [!TIP]
-> To update the README, change the `./.github/assets/README_template.md`
-
-> [!IMPORTANT]
-> Don't push your host's folder
+# Contributing to Nixy
+
+Everybody is invited and welcome to contribute to Nixy. There is a lot to do... Check the issues!
+
+The process is straight-forward.
+
+- Read [How to get faster PR reviews](https://github.com/kubernetes/community/blob/master/contributors/guide/pull-requests.md#best-practices-for-faster-reviews) by Kubernetes (but skip step 0 and 1)
+- Fork Nixy [git repository](https://github.com/anotherhadi/nixy).
+- Write your changes (new theme, bug fixes, issues fix, ...).
+- Create a Pull Request against the main branch of Nixy.
+
+> [!TIP]
+> To update the README, change the `./.github/assets/README_template.md`
+
+> [!IMPORTANT]
+> Don't push your host's folder