s&box ToolGun Pattern: Component-Based ToolMode System

Implementing a ToolGun system in s&box requires a flexible tool mode architecture that allows multiple tools (Remover, Welder, etc.) to coexist in one weapon. Challenges include:

1. Creating a pluggable tool mode system
2. Managing tool mode lifecycle (enable/disable)
3. Handling tool-specific UI and controls
4. Network-syncing active tool mode
5. Integrating with the spawn menu for tool selection