The only way I found to include icons in my Angular's application was to include glyphicons instead of fontawesome. The same problem is happening when grunt building my app with glyphicon, but the following copy task worked for me:
// Copies remaining files to places other tasks can use
copy: {
dist: {
files: [{
expand: true,
dot: true,
cwd: '<%= yeoman.app %>',
dest: '<%= yeoman.dist %>',
src: [
'*.{ico,png,txt}',
'.htaccess',
'*.html',
'views/{,*/}*.html',
'bower_components/**/*',
'images/{,*/}*.{webp}',
'fonts/*'
]
}, {
expand: true,
cwd: '.tmp/images',
dest: '<%= yeoman.dist %>/images',
src: ['generated/*']
}]
},
styles: {
expand: true,
cwd: '<%= yeoman.app %>/styles',
dest: '.tmp/styles/',
src: '{,*/}*.css'
}
},