Initial infra scaffold: watcher live on Infomaniak Public Cloud

- flake.nix exposes a devShell (openstackclient, opentofu, sops, age) plus
  nixosConfigurations.watcher (runtime) and packages.watcher-image (QCOW2
  via nixos-generators / openstack format).
- hosts/watcher/default.nix: SSH-only base, tyro user with key auth, root
  SSH disabled, trusted-users set so laptop closure pushes work.
- modules/website.nix: Caddy serves tyrolize.ch from sites/tyrolize.ch/;
  lize.ch 301-redirects; firewall opens 80/443. Let's Encrypt via HTTP-01.
- terraform/infomaniak/: OpenStack provider, security group (22/80/443),
  keypair, compute instance booted from the uploaded image. Auth via OS_*
  env vars sourced from terraform/infomaniak/.env by the devShell hook.
- scripts/build-image.sh + scripts/deploy.sh.
- dns/{tyrolize,lize}.ch.zone: full BIND zone files for the advanced view
  in Infomaniak DNS Manager; preserves kSuite mail records on lize.ch.

Watcher live at 195.15.203.200 (IPv6 2001:1600:10💯:b4e), NixOS 25.05.
HTTPS confirmed working on both domains.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

terraform/infomaniak/variables.tf

@@ -0,0 +1,36 @@
+variable "ssh_public_key" {
+  description = "Contents of ~/.ssh/id_ed25519.pub (one line, starts with 'ssh-ed25519 ...')"
+  type        = string
+}
+
+variable "ssh_key_name" {
+  description = "Display name for the keypair stored at Infomaniak"
+  type        = string
+  default     = "tyro-laptop"
+}
+
+# Flavor naming (confirmed from Infomaniak's catalogue, 2026-06):
+#   a{vCPU}_ram{GB}_disk{GB}[_perf1]
+#   _perf1 = higher-tier SSD; disk0 = bring-your-own-volume.
+# 2 vCPU / 4 GB / 20 GB SSD = a2-ram4-disk20-perf1, ~CHF 7.5/mo.
+
+variable "flavor_name" {
+  description = "OpenStack flavor for the watcher"
+  type        = string
+  default     = "a2-ram4-disk20-perf1"
+}
+
+# ext-net1 is the dual-stack public network — VMs get IPv4 + IPv6 directly.
+# ext-floating1 is only needed when running instances behind a router.
+
+variable "external_network" {
+  description = "Name of Infomaniak's public dual-stack network"
+  type        = string
+  default     = "ext-net1"
+}
+
+variable "watcher_image_name" {
+  description = "Name of the NixOS image previously uploaded to Glance"
+  type        = string
+  default     = "nixos-watcher"
+}