Improve docs on cloud playbook

skylab/infra/playbooks/cloud.yml

@@ -14,6 +14,11 @@
         suffix: tfplan
       register: _tfplan_tempfile
 
+    # Generating a plan file before yeeting a deployment into the
+    # wind helps to ensure that the syntax is correct, backend and
+    # state are valid, and all the plumbing is working as expected.
+    # We don't want errors when we deploy, so it's better to
+    # generate the plan first
     - name: Initialize terraform backend and generate plan file
       community.general.terraform:
         state: planned
@@ -24,6 +29,8 @@
         init_reconfigure: true
         plan_file: "{{ _tfplan_tempfile.path }}"
 
+    # TODO: update to take DO token from invocation args rather than
+    # implicit env var
     - name: Apply terraform plan
       community.general.terraform:
         state: present