* Allow Plex port (32400/tcp) through UFW on london-b
Plex needs direct access on port 32400 for remote streaming.
Adds common_ufw_allowed_ports to london-b host_vars.
* Add BitTorrent port (6881) to london-b UFW allowed ports
Port was already manually configured in UFW, bringing it under Ansible management.
* Configure UFW firewall rules in common Ansible role
Add UFW configuration to the common role for Debian hosts:
- Default deny incoming, allow outgoing
- Allow all traffic on tailscale0 interface (mesh comms)
- Allow SSH port 22 as safety net
- Per-host allowed ports via ufw_allowed_ports variable
- Enable UFW after rules are applied
helsinki-a gets ports 80/443 for reverse proxy traffic.
Other Debian hosts only need Tailscale + SSH.
Closes PESO-79
* Remove unused alerting and rule_files from prometheus.yml
Alerting is handled by Grafana, not Prometheus Alertmanager.
The empty alertmanagers and rule_files sections were just noise.
Resolves PESO-74
These services run on helsinki-a, not london-b. Verified via docker ps
on both hosts. deploy.yml would have managed them on the wrong host.
Fixes PESO-73
