ble: move print out of find_device()

Since this is a library function, it is best that it doesn't print. It
also lets us print a more specialized message in command line tools.

Author: dlech

pybricksdev/ble/__init__.py

@@ -39,7 +39,6 @@ async def find_device(
         asyncio.TimeoutError:
             Device was not found within the timeout.
     """
-    print(f"Searching for {name or service}")
 
     def match_uuid_and_name(device: BLEDevice, adv: AdvertisementData):
         if service not in adv.service_uuids:

pybricksdev/cli/__init__.py

@@ -144,7 +144,9 @@ async def run(self, args: argparse.Namespace):
         elif args.conntype == "ble":
             # It is a Pybricks Hub with BLE. Device name or address is given.
             hub = PybricksHub()
+            print(f"Searching for {args.name or 'any hub with Pybricks service'}...")
             device_or_address = await find_device(args.name)
+
         elif args.conntype == "usb" and args.name == "lego":
             # It's LEGO stock firmware Hub with USB.
             hub = USBRPCConnection()
@@ -195,7 +197,14 @@ async def run(self, args: argparse.Namespace):
             from ..ble import find_device
             from ..flash import BootloaderConnection
 
-            device = await find_device(service=LWP3_BOOTLOADER_SERVICE_UUID)
+            print("Searching for LEGO Bootloader...")
+
+            try:
+                device = await find_device(service=LWP3_BOOTLOADER_SERVICE_UUID)
+            except asyncio.TimeoutError:
+                print("timed out")
+                return
+
             print("Found:", device)
             updater = BootloaderConnection()
             await updater.connect(device)