Adds an OpenSpec change scoping the relocation of BRouter from the
co-located flagship (cx23, 4 GB RAM, 40 GB SSD, Europe segments only) to
a dedicated Hetzner Robot host in the same datacenter, with private
connectivity over Hetzner vSwitch #80672 (VLAN 4000).
This first PR only lays the network prerequisite:
- Terraform: a Hetzner Cloud Network (10.0.0.0/16) with a cloud subnet
(10.0.0.0/24) hosting the flagship at 10.0.0.2, and a vSwitch subnet
(10.0.1.0/24) bridged to Robot VLAN 4000. The dedicated host's VLAN
sub-interface (10.0.1.10 on enp4s0.4000) is configured out-of-band via
netplan and is not Terraform-managed.
- lifecycle { ignore_changes = [user_data] } on the flagship server to
prevent the Hetzner provider's post-1.45 user_data hash drift from
triggering a spurious full-server replacement on unrelated applies.
- OpenSpec change with proposal, design, specs (delta for
brouter-integration / infrastructure / observability /
security-hardening), and tasks; Section 1 (pre-flight) is checked off
with operator notes.
Verification: ping both directions across the vSwitch is 0% loss,
sub-ms latency; dedicated host's VLAN config persists across reboot
(verified ~60 s to restore private reachability).
Follow-up PRs will land the BRouter host compose project, Planner
shared-secret header, CD workflow retarget, observability wiring, and
the cutover.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>