Enhance crawler features and improve documentation

- Added detailed CrawlerRunConfig parameters documentation.
  - Introduced plans for real-time event-driven crawling.
  - Updated async logger default level to DEBUG for better insights.
  - Improved structure and readability in configuration file.
  - Enhanced documentation on future capabilities in new blog entries.

crawl4ai/async_logger.py

@@ -42,7 +42,7 @@ class AsyncLogger:
     def __init__(
         self,
         log_file: Optional[str] = None,
-        log_level: LogLevel = LogLevel.INFO,
+        log_level: LogLevel = LogLevel.DEBUG,
         tag_width: int = 10,
         icons: Optional[Dict[str, str]] = None,
         colors: Optional[Dict[LogLevel, str]] = None,