chore: added code comments

  let repoNodes = res.data.data.user.repositories.nodes;

  // TODO: perf improvement

  repoNodes = repoNodes

    .filter((node) => {

      return node.languages.edges.length > 0;

    })

    // flatten the list of language nodes 

    .reduce((acc, curr) => curr.languages.edges.concat(acc), [])

    .sort((a, b) => b.size - a.size)

    .reduce((acc, prev) => {

      // get the size of the language (bytes)

      let langSize = prev.size;

      // if we already have the language in the accumulator 

      // & the current language name is same as previous name

      // add the size to the language size.

      if (acc[prev.node.name] && prev.node.name === acc[prev.node.name].name) {

        langSize = prev.size + acc[prev.node.name].size;

      }