feat(web-app-magento): add Magento role + network/ports

- add role files (docs, vars, config, tasks, schema, templates)

- networks: add web-app-magento 192.168.103.208/28

- ports: add localhost http 8052

Conversation: https://chatgpt.com/share/68b8820f-f864-800f-8819-da509b99cee2

roles/web-app-magento/Installation.md

@@ -0,0 +1,30 @@
+# ⚙️ Installation & First Run
+
+## 1) Prepare DNS & Ports
+Ensure a canonical domain is mapped (e.g. `shop.{{ PRIMARY_DOMAIN }}`) and a free localhost port in `group_vars/all/10_ports.yml`:
+```
+web-app-magento: 80xx
+```
+
+## 2) Seed Credentials
+Provide (at minimum) an admin password in your inventory (vault recommended):
+```yaml
+applications:
+  web-app-magento:
+    credentials:
+      admin_password: "use-a-strong-secret"
+```
+The admin username/email are taken from `users.administrator.*`.
+
+## 3) Deploy
+Run the Infinito.Nexus playbook for your host(s). The role will:
+- Start OpenSearch (single node)
+- Start MariaDB (if `central_database` is disabled, the app-local DB is used instead)
+- Start Magento application container
+- Wire environment via `templates/env.j2`
+
+## 4) Verify
+Open your domain (e.g. `https://shop.{{ PRIMARY_DOMAIN }}`) and complete any remaining onboarding steps in the admin panel.
+
+**Admin Panel:** `{{ domains | get_url('web-app-magento', WEB_PROTOCOL) }}/admin`  
+(Default path can vary; set a custom `ADMINURI` later via `bin/magento setup:config:set` if desired.)