Fix BLE scan + touch logic + UUID + version read

- Client: change passive BLE scan to active scan (setActiveScan(true))
  Server puts name/UUID in scan response; passive scan never
  received them, so isAdvertisingService() and getName() failed.
- Server: add INPUT_PULLUP on touch pins to prevent floating
  triggers when sensors disconnected
- Server: update BLE UUID characteristic in SET_ID handler
  (pUuidChar->setValue) so reconnecting clients see correct UUID
- Server: touch logic changed from t1Active/t2Active to
  !t1Active/!t2Active (door closed = relay ON)
- Android: flushReadBuffer before VERSION? to discard stale
  boot log output; use Regex for BUILD_NR parsing
- copy_firmware.sh: copy to firmware/server/ and firmware/client/
  subdirectories to match EspFlasher.assetPath()
- version.txt: server=20 client=5

version.txt

@@ -1,2 +1,2 @@
-server=17
-client=3
+server=20
+client=5