Explore the codebase to understand how forwarding/tunnel configuration works. I need to find:

1. Frontend: The forwarding edit/create dialog component (likely in vite-frontend/src/)
2. Backend: The forwarding data model and API handlers (likely in go-backend/)
3. How the current "入口端口" (entry port) is handled

Look for:
- Files related to "forward" or "转发" or "tunnel" or "隧道"
- Data models for forwarding rules
- API handlers for creating/editing forwards

Return:
- Key file paths and their purposes
- Current data model structure for forwards
- How the entry listener is currently configured
- Any existing IP-related fields in the model