feat(crawler): add network request and console message capturing

Implement comprehensive network request and console message capturing functionality:
- Add capture_network_requests and capture_console_messages config parameters
- Add network_requests and console_messages fields to models
- Implement Playwright event listeners to capture requests, responses, and console output
- Create detailed documentation and examples
- Add comprehensive tests

This feature enables deep visibility into web page activity for debugging,
security analysis, performance profiling, and API discovery in web applications.

tests/general/test_stream_dispatch.py

@@ -0,0 +1,39 @@
+import os, sys
+# append 2 parent directories to sys.path to import crawl4ai
+parent_dir = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+sys.path.append(parent_dir)
+parent_parent_dir = os.path.dirname(parent_dir)
+sys.path.append(parent_parent_dir)
+
+
+import asyncio
+from typing import List
+from crawl4ai import *
+from crawl4ai.async_dispatcher import MemoryAdaptiveDispatcher
+
+async def test_streaming():
+    browser_config = BrowserConfig(headless=True, verbose=True)
+    crawler_config = CrawlerRunConfig(
+        cache_mode=CacheMode.BYPASS,
+        markdown_generator=DefaultMarkdownGenerator(
+            # content_filter=PruningContentFilter(
+            #     threshold=0.48, 
+            #     threshold_type="fixed", 
+            #     min_word_threshold=0
+            # )
+        ),
+    )
+
+    urls = ["http://example.com"] * 10
+    
+    async with AsyncWebCrawler(config=browser_config) as crawler:
+        dispatcher = MemoryAdaptiveDispatcher(
+            max_session_permit=5,
+            check_interval=0.5
+        )
+        
+        async for result in dispatcher.run_urls_stream(urls, crawler, crawler_config):
+            print(f"Got result for {result.url} - Success: {result.result.success}")
+
+if __name__ == "__main__":
+    asyncio.run(test_streaming())