Refactor interfaceStreams/WebSocket server/`shared.js`

[mStirner]

The solution with a shared.js file is ugly.
Move that into class.interface.js/class.device.js and expose the Map via static class methods if needed.

• Move "interfaceStreams"
• Move "interfaces"
• Move "interfaceServer"

[mStirner]

Moving this into components creates a dependency from the endpoints to the device components.
On the other hand, if you want to use/handle endponits commands/states, also the device components needs to be loaded to be able to read/write from the interface for given endpoint, so there is already a "soft" dependent.

But handling commands/states without using the device class is only possible via command.setHandler() which uses the interface from the device.