Add guarded Bluetooth CLI on/off with force override

Add get bluetooth and set bluetooth on|off, with ble aliases. Require another
active management connection before disabling Bluetooth unless off has a
trailing force argument. Keep the toggle local to the current boot.

Drain Bluetooth replies before disconnecting and recheck the remaining
connection before applying a normal shutdown. Enabling Bluetooth cancels a
pending shutdown. Document the commands and add compiled regression coverage
to CI for native USB, HWCDC, UART, network clients, force, and timer rollover.

Validation: CLI, Bluetooth, and USB regression tests passed. XIAO ESP32-S3
and RAK4631 Full Companion builds passed RAM, flash, and capability checks.

.github/workflows/run-unit-tests.yml

@@ -125,6 +125,9 @@ jobs:
       - name: Verify Companion contact persistence and OTA sleep guards
         run: python3 -B test/test_companion_contact_sleep_contract.py -v
 
+      - name: Verify Companion Bluetooth CLI connection protection
+        run: python3 -B test/test_companion_bluetooth_control.py -v
+
       - name: Verify message reader buttons, touch targets, and footer layouts
         working-directory: test
         run: >-