State-Machine and Workflow Driven Website System with 3D Avatar as Interaction and Presentation Layer (Not System Core)

This is a full website system engineering project.
It is NOT a 3D demo and NOT a simple frontend task.

The following technical premises must be clearly understood and accepted:

1. Definition of the system core (non-negotiable)
The system core is the website system itself, including:
- A clear, extensible, and maintainable state machine
- State-driven workflow control and logic branching
- System-level logging and state tracking
- Clear module boundaries and an extensible architecture

All business logic, workflow execution, state transitions,
and decision-making are handled entirely by the system layer.
The 3D avatar does NOT participate in business logic,
does NOT drive the state machine,
and does NOT advance system workflows.

2. Definition of the 3D avatar role
The 3D avatar exists only as a frontend interaction
and presentation layer.
It is used to present system states, guide users,
and display execution feedback.

Although the 3D avatar is not the system core,
it is NOT decorative and must be real, runnable, and demonstrable.

3. Mandatory 3D avatar capabilities (must be implemented)
The 3D avatar must be able to:
- Appear on the website interface (web environment)
- Walk or move within the scene
- Perform basic facial expressions
- Speak with lip-sync (voice-driven or text-driven)
- Perform basic gestures, pointing, or guidance actions
- React to system states or system events with different visual behaviors

Important:
All 3D behaviors are triggered by system states or events,
but system states are NEVER driven by the 3D avatar.
This is a strict one-way relationship: system → 3D presentation.

4. Mandatory system-layer capabilities (non-3D)
The system layer must include:
- A real state machine implementation (not conceptual)
- At least one fully demonstrable system workflow
- Logging of state changes and workflow execution
- Logs that can be used to verify system behavior
- A clear loading and initialization flow (loader)

5. Plugin / extension capability
The system must reserve and explain a plugin / extension mechanism
for future expansion.
In the prototype stage, a minimal working example is acceptable,
but it must be real, not conceptual.

6. Project nature
This is a system engineering project that requires the ability
to implement and coordinate:
- Website system engineering
- State machines and workflow control
- Decoupled system and frontend architecture
- Integration between system states and a 3D avatar
without allowing the 3D layer to control the system

If you cannot clearly distinguish between
the system core and the 3D presentation layer,
or if you believe a 3D avatar should act as the system driver,
please do not respond to this project. Show More