Cut the comment bloat from the Podman playbooks

Comment blocks now stay within three lines and explain only the non-obvious. Long histories, include examples, and commented-out code are gone. No task, key, or value changed; the only data change is comment text inside the generated unit files.

wikijs/playbook.yml

@@ -1,28 +1,5 @@
 ---
-# Wiki.js as a rootless Podman Quadlet unit, behind the shared Caddy unit
-# (caddy/playbook.yml) and with its data in the shared Postgres unit
-# (postgres/playbook.yml).
-#
-# Connects as the container user and runs everything as that user: the Quadlet
-# units belong to it, so the connection's PAM session is what makes
-# `systemctl --user` work without any environment juggling.
-#
-# gather_facts is required: podman_user and the home directory come from the
-# user_id / user_dir facts.
-#
-# The rootless-Podman prerequisites (installing podman, enabling lingering, the
-# low-port sysctl, creating the Quadlet directory) are deliberately NOT applied
-# here. They are the shared task file at caddy/roles/podman/tasks/main.yaml, and
-# a host that has already run caddy/playbook.yml has them:
-#
-#   - name: Rootless Podman prerequisites
-#     ansible.builtin.include_tasks: "{{ playbook_dir }}/../caddy/roles/podman/tasks/main.yaml"
-#
-# The variables this play needs are duplicated at the top of vars/default.yml, so
-# it stands on its own. (Applying the commented include above would also need
-# podman_unprivileged_port_start, which lives in caddy/vars/default.yml.)
-#
-# Run with: ansible-playbook -u tanshu wikijs/playbook.yml
+# Requires caddy and postgres to have run first.
 - name: Deploy Wiki.js as a rootless Podman Quadlet
   hosts: emily
   gather_facts: true
@@ -30,25 +7,11 @@
     - vars/default.yml
 
   pre_tasks:
-    # This must happen before the app unit is started, not after: the generated
-    # unit references {{ network_name }}.network, and Quadlet fails *unit
-    # generation* (so `systemctl --user start` reports "unit not found") when a
-    # referenced .network file does not exist yet. The same include writes the
-    # Caddy-side drop-in that attaches Caddy to this network, and the Postgres
-    # attach below needs the network unit to exist as well.
-    #
-    # network_name is a play var, so the include can see it directly.
+    # Quadlet needs the network unit before it generates the app unit.
     - name: Register Wiki.js's network with Caddy
       ansible.builtin.include_tasks: "{{ playbook_dir }}/../caddy/roles/register/tasks/main.yaml"
 
   roles:
-    # Attaches this app's network to the shared Postgres unit, which is what
-    # makes DB_HOST=db resolve, and owns the "Restart Postgres" handler that
-    # postgres/roles/attach notifies. Runs first so the database is reachable
-    # before the app starts.
     - postgres
-    # The app: content and upload directories, the 0600 environment file, the
-    # Quadlet unit, start + verify.
     - wikijs
-    # Appends this site's block to the shared Caddyfile and reloads Caddy.
     - caddy