Grunt error when running Sails.js app in Amazon ElasticBeanstalk - node.js

Question

I am moving a Sails.js app hosted on Heroku to Amazon ElasticBeanstalk. When the application launches, it throws the following Grunt error (pulled from eb logs):
info: Sails <| .-..-.
info: v0.11.5 |\
info: /|.\
info: / || \
info: ,' |' \
info: .-'.-==|/_--'
info: `--'-------'
info: __---___--___---___--___---___--___
info: ____---___--___---___--___---___--___-__
info:
info: Server lifted in `/var/app/current`
info: To see your app, visit http://localhost:8081
info: To shut down Sails, press <CTRL> + C at any time.
debug: --------------------------------------------------------
debug: :: Mon Feb 29 2016 08:21:46 GMT+0000 (UTC)
debug: Environment : development
debug: Port : 8081
debug: --------------------------------------------------------
error: ** Grunt :: An error occurred. **
error:
------------------------------------------------------------------------
>> FileError: '../bower_components/bootstrap/less/grid.less' wasn't found in assets/styles/importer.less on line 9, column 1:
>> 8 // Import Bootstrap
>> 9 #import "../bower_components/bootstrap/less/grid.less";
>> 10 #import "../bower_components/bootstrap/less/mixins.less";
Warning: Error compiling assets/styles/importer.less
Aborted due to warnings.
Running "less:dev" (less) task
------------------------------------------------------------------------
error: Looks like a Grunt error occurred--
error: Please fix it, then **restart Sails** to continue running tasks (e.g. watching for changes in assets)
error: Or if you're stuck, check out the troubleshooting tips below.
error: Troubleshooting tips:
error:
error: *-> Are "grunt" and related grunt task modules installed locally? Run `npm install` if you're not sure.
error:
error: *-> You might have a malformed LESS, SASS, CoffeeScript file, etc.
error:
error: *-> Or maybe you don't have permissions to access the `.tmp` directory?
error: e.g., `/var/app/current/.tmp` ?
error:
error: If you think this might be the case, try running:
error: sudo chown -R 497 /var/app/current/.tmp
The same code runs fine on my local development laptop and on Heroku but not on ElasticBeanstalk. Why is it unable to find the bootstrap files? This being a PaaS, I can't even run the recommended sudo chown command that the log recommended. Also to be clear, I have the following command in my package.json file:
"scripts": {
"postinstall": "bower install; grunt build",
"debug": "node debug app.js",
"start": "node app.js"
}
I have instructed the script to run bower install after the NPM packages are installed in the machine. None of the images in my /assets folder seem to load either. Not sure what's going on. Please help.