feat(ops/dns): manage snix.{store,systems} in DO

Also include tvix.{store,systems}, they might still be used in some
places.

Change-Id: I90085d7488f94c8764e61e3d99d8f03459c6f9f0
Reviewed-on: https://cl.snix.dev/c/snix/+/30501
Reviewed-by: Ryan Lahfa <ryan@lahfa.xyz>
Autosubmit: Florian Klink <flokli@flokli.de>
Tested-by: besadii

ops/dns/snix-store.tf

@@ -0,0 +1,31 @@
+# DNS configuration for snix.store
+
+resource "digitalocean_domain" "snix_store" {
+  name = "snix.store"
+}
+
+resource "digitalocean_record" "snix_store_nixos_v4" {
+  domain   = digitalocean_domain.snix_store.id
+  type     = "A"
+  name     = "nixos"
+  value    = "37.27.128.134"
+}
+
+resource "digitalocean_record" "snix_store_nixos_v6" {
+  domain   = digitalocean_domain.snix_store.id
+  type     = "AAAA"
+  name     = "nixos"
+  value    = "2a01:4f9:3071:1091::2"
+}
+
+# tvix.store, old alias
+resource "digitalocean_domain" "tvix_store" {
+  name = "tvix.store"
+}
+
+resource "digitalocean_record" "tvix_store_nixos_cname" {
+  domain   = digitalocean_domain.tvix_store.id
+  type     = "CNAME"
+  name     = "nixos"
+  value    = "nixos.snix.store."
+}