Role-Based Booking & Chat

I need a vanilla-PHP solution that plugs straight into our HR platform and lets four roles—Main Admin, Sub Admin, Consultant, and Client—handle bookings and exchange messages. Please work only with core PHP and MySQL; no frameworks. The interface should be responsive through plain HTML, CSS, and Bootstrap. A classic page-reload approach is fine for the chat, so AJAX or WebSockets are optional rather than required.

Core workflow
• Clients submit a booking form (service, date, time, notes).
• The system stores client, consultant, service, date, and status.
• Dashboards show each user only the bookings and chats that match their role.
• Messaging is saved in the database and respects the same role rules (Admins with everyone, Consultants with assigned Clients, etc.).

Access & security
Authentication must be handled through a standard email-and-password login. During registration I need to collect (and validate) full name, email, username, password, and phone number.

Deliverables
• Complete, well-commented PHP, HTML, CSS, and JS source code
• MySQL schema and a .sql dump ready for import
• A concise setup guide explaining database import, config values, and any file permissions

If you follow the role matrix precisely, keep the code framework-free, and supply the deliverables above, that will count as acceptance.