feat(ops/secrets): Import secrets for tf-glesys

Adds the secrets and some instructions for deploying the GleSYS
Terraform infrastructure.

Change-Id: I1a10f9cee7648d406b3d27ef45fc74b6923cbc30
Reviewed-on: https://cl.tvl.fyi/c/depot/+/4712
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>

ops/glesys/README.md

@@ -0,0 +1,20 @@
+Terraform for GleSYS
+======================
+
+This contains the Terraform configuration for deploying TVL's
+infrastructure at [GleSYS](https://glesys.com). This includes object
+storage (e.g. for backups and Terraform state) and DNS.
+
+Secrets are needed for applying this. The encrypted file
+`//ops/secrets/tf-glesys.age` contains `export` calls which should be
+sourced, for example via `direnv`, by users with the appropriate
+credentials.
+
+An example `direnv` configuration used by tazjin is this:
+
+```
+# //ops/secrets/.envrc
+source_up
+eval $(age --decrypt -i ~/.ssh/id_ed25519 $(git rev-parse --show-toplevel)/ops/secrets/tf-glesys.age)
+watch_file $(git rev-parse --show-toplevel)/secrets/tf-glesys.age
+```

ops/secrets/secrets.nix

@@ -30,5 +30,6 @@ in {
   "nix-cache-pub.age" = default;
   "owothia.age" = default;
   "panettone.age" = default;
+  "tf-glesys.age" = default;
   "tf-keycloak.age" = default;
 }