How to do code splitting in the right way?

Question

I'm working on Vue project. I really confused about what a proper code-splitting and spaghetti code looks like in javascript.

Some of my team said, my code is confusing and tell me to learn more about code-splitting to prevent spaghetti code. I have done it by this, taken from a Vuex store I've refactored:

import VueCookies from 'vue-cookies'

export default {
  state: {
    destinations: [],
    excluded: [],
    isBroadcasting: false,
    sent: 0,
    fails: 0,
  },
  mutations: {
    /**
     * Notify the user that the broadcasting event is started.
     * 
     * @author Donny Pratama <donnypratama1024@gmail.com>
     * @param {Object} state Vuex state
     * @returns void
     */
    START_BROADCASTING(state) {
      state.isBroadcasting = true
    },

    /**
     * Set broadcast destinations.
     * 
     * @author Donny Pratama <donnypratama1024@gmail.com>
     * @param {Object} state Vuex state
     * @param {Array} destinations Collection of destinations
     * @returns void
     */
    SET_BROADCAST_DESTINATIONS(state, destinations) {
      state.destinations = destinations
    },

    /**
     * Set the excluded destinations.
     * 
     * @param {Object} state Vuex state
     * @param {Array} excluded Collection of the excluded destinations
     */
    SET_BROADCAST_EXCLUSION(state, excluded) {
      state.excluded = excluded
    },

    /**
     * Count how many message has been sent.
     * 
     * @author Donny Pratama <donnypratama1024@gmail.com>
     * @param {Object} state Vuex state
     * @returns void
     */
    ON_BROADCAST_SUCCESS(state) {
      state.sent++
    },

    /**
     * Count how many messages has been failed to send.
     * 
     * @author Donny Pratama <donnypratama1024@gmail.com>
     * @param {Object} state Vuex state
     * @returns void
     */
    ON_BROADCAST_FAILED(state) {
      state.fails++
    },

    /**
     * Notify the user that the broadcast process has been done.
     * 
     * @author Donny Pratama <donnypratama1024@gmail.com>
     * @param {Object} state Vuex state
     * @returns void
     */
    END_BROADCASTING(state) {
      state.isBroadcasting = false
    }
  },
  actions: {
    /**
     * Start broadcasting.
     * 
     * @param {Object} context Vuex context
     * @param {String} message Message to be broadcasted
     */
    startBroadcast(context, message) {
      let destinations = context.dispatch('mapWithout', context.state.excluded)

      context.commit('START_BROADCASTING')
      context.dispatch('send', { message, destinations })
    },

    /**
     * Make a post data.
     * 
     * @author Donny Pratama <donnypratama1024@gmai.com>
     * @param {Object} destination Contact destination
     * @returns {Object} { from, to, message, type }
     */
    make(payload) {
      return {
        from: VueCookies.get('active_project').projectPhoneNumber,
        message: payload.message,
        type: 'text',
        to: payload.destination.id._serialized,
      }
    },

    /**
     * Map destination without the excluded.
     * 
     * @author Donny Pratama <donnypratama1024@gmail.com>
     * @param {Object} context Vuex context
     * @param {Array} excluded Array of destination to be excluded
     * @returns {Array} destinations
     */
    mapWithout(context, excluded) {
      return _.without(context.state.destinations, excluded)
    },

    /**
     * Notify when the broadcast process is done via [state.isBroadcasting].
     * @param {Object} payload Current index and destinations array
     */
    notifyWhenDone(payload) {
      if (payload.index === payload.destinations.length) {
        context.commit('END_BROADCASTING')
      }
    },

    /**
     * Send message to destinations.
     * 
     * @author Donny Pratama <donnypratama1024@gmail.com>
     * @param {Object} payload Message and destinations
     * @returns void
     */
    send(payload) {
      payload.destinations.forEach((destination, index) => {
        let data = context.dispatch('make', {
          message: payload.message,
          destination: destination
        })

        axios.post(`sendMessage`, data)
          .then((_) => context.commit('ON_BROADCAST_SUCCESS'))
          .catch((_) => context.commit('ON_BROADCAST_FAILED'))

        context.dispatch('notifyWhenDone', {
          index: index,
          destinations: payload.destinations
        })
      })
    },
  }
}

I need your opinion, am I doing it the right way?