- User systemd with linger, uvicorn --reload from bare repo worktree
- Vendor files (diff2html) fetched and symlinked at startup
- kannix-ctl wrapper script in user packages

- Add kannix flake input (local git repo)
- 2configs/kannix.nix: kannix service on port 4243, nginx at kannix.lassul.us
- Git integration enabled (repos + worktrees in /var/lib/kannix/)
- SSH keys for kannix user
- Backup updated: /var/lib/kannix instead of /var/lib/kanvibe

Disable the AWS harvester in jitsi-videobridge since it is not needed
for self-hosted setups.

Add ULA prefix fd42:7d6a::/64 on int0 with IPv6 Router Advertisement
so clients get IPv6 via SLAAC. Enable IPv6 forwarding and NAT66
masquerade for the ULA prefix. This fixes Jitsi (and other IPv6-only
services) not working from the internal network.