Virtual WiFi/Bluetooth environment + bridge-to-real mode

[Kinin-Code-Offical]

Goal: Provide a simulated WiFi/BLE environment on the host that can be switched between:

• Virtual RF environment (simulated APs/clients, packet loss, latency)
• Bridge-to-real host network/Bluetooth when desired

Acceptance:

• Works for both Arduino-class (when modeled) and RPi QEMU guest.
• Clean enable/disable; no always-on background cost.