fix: Initialize default logger in AsyncPlaywrightCrawlerStrategy

Fixes #1704

When AsyncPlaywrightCrawlerStrategy is instantiated without a logger,
self.logger remains None, causing crashes when logger methods are called
(e.g., during screenshot/PDF/MHTML export).

Changed to initialize a default AsyncLogger(verbose=False) when no logger
is provided, preventing NoneType errors throughout the strategy.

Co-Authored-By: Claude <noreply@anthropic.com>

crawl4ai/async_crawler_strategy.py

@@ -87,7 +87,8 @@ class AsyncPlaywrightCrawlerStrategy(AsyncCrawlerStrategy):
         """
         # Initialize browser config, either from provided object or kwargs
         self.browser_config = browser_config or BrowserConfig.from_kwargs(kwargs)
-        self.logger = logger
+        # Initialize with default logger if none provided to prevent NoneType errors
+        self.logger = logger if logger is not None else AsyncLogger(verbose=False)
         
         # Initialize browser adapter
         self.adapter = browser_adapter or PlaywrightAdapter()