You can add clientlibs folder under each component and add category name to clientlibs folder like below
Add the clientlibs inside component jsp/html
<cq:includeClientLib categories="categoryname" /> -- This includes both js/css files
<cq:includeClientLib js="categoryname"/> -- To include only js
<cq:includeClientLib css="categoryname"/> -- To include only css
This will include multiple js/css files on the page as each component will include a js/css files. Also, if clientlibs are added in /apps user everyone should have read access of /apps for files to load in publisher or clientlibs needs to create under /etc/designs
Also, this solution injects clientlibs in the body of the page, which defeats the purpose of a component-based architecture (increasing the performance of an app) by forcing the client to re-render the page. And adding <link .. /> to the body is invalid, 'link' tags should only be added in the head of a document.