Load JS files before anything else (jQuery and other JS libraries)

I will reply to myself because I figured out a solution.

The transpile process was giving errors because the $ and the functions html5_qrcode and html5_qecode_stop were not being read from the JS files that I included in index.html in time. They were eventually, but not a the time the page .ts was being processed.

I bypassed the transpiler error by declaring both in the page .ts file (like you would with prototypes):

declare var $: any;
declare function html5_qrcode(any);
declare function html5_qrcode_stop(any);

Not sure it’s the best solution, but it is one.
Hope this helps someone