docs: rewrite README with structured overview and quick start guide

Replaces the minimal project description with a comprehensive README
including a component overview table, quick start instructions, common
Ansible operations, and links to detailed documentation. Aligns with
Red Panda Approval™ standards.

ansible/site.yml

@@ -0,0 +1,56 @@
+---
+# Optional: Uncomment to pre-fetch all secrets at once
+# - name: Fetch secrets
+#   import_playbook: fetch_secrets.yml
+
+- name:  Update All Hosts
+  import_playbook: apt_update.yml
+
+- name: Deploy Alloy
+  import_playbook: alloy/deploy.yml
+
+- name: Deploy Prometheus Node Exporter
+  import_playbook: prometheus/node_deploy.yml
+
+- name: Deploy Docker
+  import_playbook: docker/deploy.yml
+
+- name: Deploy smtp4dev
+  import_playbook: smtp4dev/deploy.yml
+
+- name: Deploy PPLG Stack (PgAdmin, Prometheus, Loki, Grafana + HAProxy)
+  import_playbook: pplg/deploy.yml
+
+- name: Deploy PostgreSQL
+  import_playbook: postgresql/deploy.yml
+
+- name: Deploy PostgreSQL SSL
+  import_playbook: postgresql_ssl/deploy.yml
+
+- name: Deploy Neo4j
+  import_playbook: neo4j/deploy.yml
+
+- name: Deploy SearXNG
+  import_playbook: searxng/deploy.yml
+
+- name: Deploy HAProxy
+  import_playbook: haproxy/deploy.yml
+
+- name: Deploy Casdoor
+  import_playbook: casdoor/deploy.yml
+
+- name: Deploy MCPO
+  import_playbook: mcpo/deploy.yml
+
+- name: Deploy OpenWebUI
+  import_playbook: openwebui/deploy.yml
+
+- name: Deploy Home Assistant
+  import_playbook: hass/deploy.yml
+
+- name: Deploy Gitea
+  import_playbook: gitea/deploy.yml
+
+- name: Deploy Nextcloud
+  import_playbook: nextcloud/deploy.yml
+