now using bitwise operators and dividing the `rights` value so you can have other rights whilst having the `OPERATOR` right

for example: `3` is `1` and `2` combined

NOTE: a potential issue has been uncovered while testing; if you have more than 1 thread the server will only stop 1 thread and the rest of the server will continue to run

updated stop.ts so it checks for user rights instead of the SYSTEM flag which can possibly cause some unnecessary complications when it comes to instance management

*also has been tested with multiple tokens to be sure that this does NOT permit normal users to POST to the /stop API route
**NOTE**: instance owners will have to re-run `npm run setup` for these changes to take effect

Co-authored-by: Erkin Alp Güney <erkinalp9035@gmail.com>

patched up the route and polished it

note: THIS API IS ONLY FOR DEVELOPMENT PURPOSES