mock

The reference driver runs device files in memory and is left out of the driver counts.

Tier	Reference
Protocol	in-memory simulation
Covers	simulated desk fan, simulated heater, any device file for testing and demos
Hazard default	low
Conformance	control
Tested with	reference driver for the conformance suite

Estimated reach. None (simulation only). The mock driver never talks to hardware and runs any device file in memory for tests, demos and the website playground.

This driver has no documentation page yet. Add docs/drivers/mock.md as the driver contract describes.