feat(browser): implement modular browser management system

Adds a new browser management system with strategy pattern implementation:
- Introduces BrowserManager class with strategy pattern support
- Adds PlaywrightBrowserStrategy, CDPBrowserStrategy, and BuiltinBrowserStrategy
- Implements BrowserProfileManager for profile management
- Adds PagePoolConfig for browser page pooling
- Includes comprehensive test suite for all browser strategies

BREAKING CHANGE: Browser management has been moved to browser/ module. Direct usage of browser_manager.py and browser_profiler.py is deprecated.

tests/browser/test_combined.py

@@ -0,0 +1,77 @@
+"""Combined test runner for all browser module tests.
+
+This script runs all the browser module tests in sequence and
+provides a comprehensive summary.
+"""
+
+import asyncio
+import os
+import sys
+import time
+
+# Add the project root to Python path if running directly
+if __name__ == "__main__":
+    sys.path.insert(0, os.path.abspath(os.path.join(os.path.dirname(__file__), '../..')))
+
+from crawl4ai.async_logger import AsyncLogger
+
+# Create a logger for clear terminal output
+logger = AsyncLogger(verbose=True, log_file=None)
+
+async def run_test_module(module_name, header):
+    """Run all tests in a module and return results."""
+    logger.info(f"\n{'-'*30}", tag="TEST")
+    logger.info(f"RUNNING: {header}", tag="TEST")
+    logger.info(f"{'-'*30}", tag="TEST")
+    
+    # Import the module dynamically
+    module = __import__(f"tests.browser.{module_name}", fromlist=["run_tests"])
+    
+    # Track time for performance measurement
+    start_time = time.time()
+    
+    # Run the tests
+    await module.run_tests()
+    
+    # Calculate time taken
+    time_taken = time.time() - start_time
+    logger.info(f"Time taken: {time_taken:.2f} seconds", tag="TIMING")
+    
+    return time_taken
+
+async def main():
+    """Run all test modules."""
+    logger.info("STARTING COMPREHENSIVE BROWSER MODULE TESTS", tag="MAIN")
+    
+    # List of test modules to run
+    test_modules = [
+        ("test_browser_manager", "Browser Manager Tests"),
+        ("test_playwright_strategy", "Playwright Strategy Tests"),
+        ("test_cdp_strategy", "CDP Strategy Tests"),
+        ("test_builtin_strategy", "Builtin Browser Strategy Tests"),
+        ("test_profiles", "Profile Management Tests")
+    ]
+    
+    # Run each test module
+    timings = {}
+    for module_name, header in test_modules:
+        try:
+            time_taken = await run_test_module(module_name, header)
+            timings[module_name] = time_taken
+        except Exception as e:
+            logger.error(f"Error running {module_name}: {str(e)}", tag="ERROR")
+    
+    # Print summary
+    logger.info("\n\nTEST SUMMARY:", tag="SUMMARY")
+    logger.info(f"{'-'*50}", tag="SUMMARY")
+    for module_name, header in test_modules:
+        if module_name in timings:
+            logger.info(f"{header}: {timings[module_name]:.2f} seconds", tag="SUMMARY")
+        else:
+            logger.error(f"{header}: FAILED TO RUN", tag="SUMMARY")
+    logger.info(f"{'-'*50}", tag="SUMMARY")
+    total_time = sum(timings.values())
+    logger.info(f"Total time: {total_time:.2f} seconds", tag="SUMMARY")
+
+if __name__ == "__main__":
+    asyncio.run(main())