Add new web-app-mini-qr role

- Introduced new role 'web-app-mini-qr' to deploy the lightweight, self-hosted Mini-QR application.
- Added dedicated subnet and localhost port mapping (8059) in group_vars.
- Ensured proper dependency structure and run_once handling in MIG role.
- Included upstream reference and CSP whitelist for temporary clarity.ms removal tracking.
- Added README.md and meta information following the Infinito.Nexus web-app schema.

See: https://chatgpt.com/share/68f890ab-5960-800f-85f8-ba30bd4350fe

group_vars/all/10_ports.yml

@@ -80,6 +80,7 @@ ports:
       web-app-flowise: 8056
       web-app-minio_api: 8057
       web-app-minio_console: 8058
+      web-app-mini-qr: 8059
       web-app-bigbluebutton: 48087    # This port is predefined by bbb. @todo Try to change this to a 8XXX port
   public:
     # The following ports should be changed to 22 on the subdomain via stream mapping