feat: add cache control

[tetuaoro]

Description

Due to google analytics and page speed insights check-up, remove the warning by adding a cache policy to the header of injected script.

Change

• [x] set cache control header with max-age of 1 year for script.js

[tetuaoro]

Hi shynet.

Ah, I edited recently my fork and seems the pr has closed by the rules. Could you re-open this pr please ?!

Thanks :+1: