chore: Add action to set dark mode from the react-native-widget (#7167)

Co-authored-by: Pranav Raj S <pranav@chatwoot.com>

app/javascript/widget/store/modules/appConfig.js

@@ -1,5 +1,6 @@
 import {
   SET_BUBBLE_VISIBILITY,
+  SET_COLOR_SCHEME,
   SET_REFERRER_HOST,
   SET_WIDGET_APP_CONFIG,
   SET_WIDGET_COLOR,
@@ -55,6 +56,9 @@ export const actions = {
   setWidgetColor({ commit }, widgetColor) {
     commit(SET_WIDGET_COLOR, widgetColor);
   },
+  setColorScheme({ commit }, darkMode) {
+    commit(SET_COLOR_SCHEME, darkMode);
+  },
   setReferrerHost({ commit }, referrerHost) {
     commit(SET_REFERRER_HOST, referrerHost);
   },
@@ -83,6 +87,9 @@ export const mutations = {
   [SET_BUBBLE_VISIBILITY]($state, hideMessageBubble) {
     $state.hideMessageBubble = hideMessageBubble;
   },
+  [SET_COLOR_SCHEME]($state, darkMode) {
+    $state.darkMode = darkMode;
+  },
 };
 
 export default {