fix: replace blocking time.sleep with await asyncio.sleep in WhatsApp connect

time.sleep(1) inside async def connect() blocks the entire event loop.
Replaced with await asyncio.sleep(1) to properly yield control.

Authored by 0xbyt4. Fixes blocking sleep in WhatsApp bridge startup.

Co-authored-by: 0xbyt4 <0xbyt4@users.noreply.github.com>

gateway/platforms/whatsapp.py

@@ -181,8 +181,8 @@ class WhatsAppAdapter(BasePlatformAdapter):
             
             # Kill any orphaned bridge from a previous gateway run
             _kill_port_process(self._bridge_port)
-            import time
-            time.sleep(1)
+            import asyncio
+            await asyncio.sleep(1)
             
             # Start the bridge process in its own process group.
             # Route output to a log file so QR codes, errors, and reconnection