incl. a calculator, a hash encoder + rot13 and b64!, and a "what time is it" with timezone selection
frontend injected in $payload["left"] in web.php
you can see this live [on my instance](https://4get.silly.computer/web?s=7%2B8(9%5E2)&scraper=brave&nsfw=yes) (there are some issues that aren't related to this PR. favicons, etc. I'll fix them later.)
Reviewed-on: #10
Co-authored-by: cynic <admin@cynic.moe>
Co-committed-by: cynic <admin@cynic.moe>
