Deploy Anubis for DevCentral

Summary:
Integrate Anubis as a WAF/Reverse Proxy to secure traffic
and challenge AI scrapers.

[ SELinux policy ]

Allow nginx to connect to UNIX socket.

Ref T2193.

Test Plan:
Initial proof of concept verified on Dwellers.

Tests for production:

• Anubis service starts and populates socket
• Sockets permissions are correct
• It's possible to connect to the socket and get challenge, then site
• Bot policies correctly filter and challenge traffic via curl tests
• nginx redirects correctly to Anubis instead of the site directly

Reviewed By: dereckson

Differential Revision: https://devcentral.nasqueron.org/D3908

Signed-off-by: Sébastien Santoro <dereckson@espace-win.org>