feat: implement comprehensive variable management system

- Create standardized group_vars directory structure
- Add domains.yml with centralized subdomain mappings
- Add infrastructure.yml with network, SMTP, and path config
- Reorganize vault.yml secrets by service with consistent naming
- Update 15+ Docker compose templates to use new variable structure
- Simplify playbook commands by removing --extra-vars requirement
- Replace hardcoded domains/IPs with template variables
- Standardize secret references across all services

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

roles/docker/templates/paperlessngx.env.j2

@@ -24,11 +24,11 @@
 
 # This is required if you will be exposing Paperless-ngx on a public domain
 # (if doing so please consider security measures such as reverse proxy)
-PAPERLESS_URL=https://paper.thesatelliteoflove.com
+PAPERLESS_URL=https://{{ subdomains.papers }}
 
 # Adjust this key if you plan to make paperless available publicly. It should
 # be a very long sequence of random characters. You don't need to remember it.
-PAPERLESS_SECRET_KEY={{ paperlessngx_secret }}
+PAPERLESS_SECRET_KEY={{ vault_paperlessngx.secret_key }}
 
 # Use this variable to set a timezone for the Paperless Docker containers. If not specified, defaults to UTC.
 PAPERLESS_TIME_ZONE=America/Denver
@@ -43,4 +43,4 @@ PAPERLESS_TIME_ZONE=America/Denver
 
 # authentik
 PAPERLESS_APPS: "allauth.socialaccount.providers.openid_connect"
-PAPERLESS_SOCIALACCOUNT_PROVIDERS: '{"openid_connect": {"APPS": [{"provider_id": "authentik","name": "Authentik SSO","client_id": "{{ paperless_oauth_client_id }}","secret": "{{ paperless_oauth_client_secret }}","settings": { "server_url": "https://auth.thesatelliteoflove.com/application/o/paperlessngx/.well-known/openid-configuration"}}]}}'
+PAPERLESS_SOCIALACCOUNT_PROVIDERS: '{"openid_connect": {"APPS": [{"provider_id": "authentik","name": "Authentik SSO","client_id": "{{ vault_paperlessngx.oidc.client_id }}","secret": "{{ vault_paperlessngx.oidc.client_secret }}","settings": { "server_url": "https://{{ subdomains.auth }}/application/o/paperlessngx/.well-known/openid-configuration"}}]}}'