state man. API && modularisation

- adds functions
  - util_create_state
  - util_read_state
  - util_write_state
  - util_delete_state
for state management API. see docs/about_states.md for details.

- moves functions from _reve.sh to _reve_utils.sh to prevent circular
imports.

chores/misc/asus_kbd_light.sh

@@ -0,0 +1,27 @@
+#!/usr/bin/env bash
+
+# reve                              desktop environment framework
+# Yigid BALABAN <fyb@fybx.dev>                               2024
+
+# chore script
+# type      misc
+# name      asus_kbd_light.sh
+# desc      ...
+# vars      ...
+# reload    ...
+
+reve_folder="$HOME/.config/reve"
+reve_desktop_mode="$reve_folder/desktop_mode"
+
+source "$( reve -w )/_reve"
+
+current_mode=$( util_readf "$reve_desktop_mode" )
+
+if [ "$current_mode" == "light" ]; then
+    exit 0
+fi
+
+hex_dominant_color=$( magick "$reve_folder/chore/bg_dark" -resize 1x1\! -format "%[hex:p{0,0}]" info: )
+
+asusctl led-mode static -c "$hex_dominant_color"
+asusctl --kbd-bright med

chores/mode/display_brightness.sh

@@ -0,0 +1,20 @@
+#!/usr/bin/env bash
+
+# reve                              desktop environment framework
+# Yigid BALABAN <fyb@fybx.dev>                               2024
+
+# chore script
+# type      mode
+# name      display_brightness.sh
+# desc      sets display brightness depending on the desktop_mode
+# vars      day_level, night_level
+# reload    none
+
+# shellcheck source=../../_reve.sh
+source "$(reve where)/_reve"
+
+if [ "$RV_CURRENT_MODE" == "dark" ]; then
+  brightnessctl set "$(util_read_config display.night_level)"
+else
+  brightnessctl set "$(util_read_config display.day_level)"
+fi

chores/mode/swww_slideshow.sh

@@ -0,0 +1,22 @@
+#!/bin/bash
+
+# reve                              desktop environment framework
+# Yigid BALABAN <fyb@fybx.dev>                               2024
+
+# chore script
+# type      mode
+# name      swww-based wallpaper slideshow
+# desc      reruns utility/swww_slideshow when mode changes
+# vars      swwwss.dark, swwwss.light, swwwss.folder
+# reload    no
+
+# shellcheck source=../../_reve.sh
+source "$(reve where)/_reve"
+
+desktop_mode=$(util_read_config base.desktop_mode)
+
+if [ "$desktop_mode" == "dark" ]; then
+  util_write_config swwwss.folder "$(util_read_config swwwss.dark)"
+else
+  util_write_config swwwss.folder "$(util_read_config swwwss.light)"
+fi