refactor(crawling): improve type hints and code cleanup

- Added proper return type hints for DeepCrawlStrategy.arun method
- Added __call__ method to DeepCrawlStrategy for easier usage
- Removed redundant comments and imports
- Cleaned up type hints in DFS strategy
- Removed empty docker_client.py and .continuerules
- Added .private/ to gitignore

BREAKING CHANGE: DeepCrawlStrategy.arun now returns Union[CrawlResultT, List[CrawlResultT], AsyncGenerator[CrawlResultT, None]]

crawl4ai/deep_crawling/base_strategy.py

@@ -94,7 +94,7 @@ class DeepCrawlStrategy(ABC):
             crawler_run_config (Optional[CrawlerRunConfig]): Crawler configuration.
         
         Returns:
-            AsyncGenerator[CrawlResult, None]: An async generator yielding crawl results.
+            Union[CrawlResultT, List[CrawlResultT], AsyncGenerator[CrawlResultT, None]]
         """
         if config is None:
             raise ValueError("CrawlerRunConfig must be provided")
@@ -104,6 +104,9 @@ class DeepCrawlStrategy(ABC):
         else:
             return await self._arun_batch(start_url, crawler, config)
 
+    def __call__(self, start_url: str, crawler: AsyncWebCrawler, config: CrawlerRunConfig):
+        return self.arun(start_url, crawler, config)
+
     @abstractmethod
     async def shutdown(self) -> None:
         """