feat(docker): add Docker service integration and config serialization

Add Docker service integration with FastAPI server and client implementation.
Implement serialization utilities for BrowserConfig and CrawlerRunConfig to support
Docker service communication. Clean up imports and improve error handling.

- Add Crawl4aiDockerClient class
- Implement config serialization/deserialization
- Add FastAPI server with streaming support
- Add health check endpoint
- Clean up imports and type hints

crawl4ai/async_webcrawler.py

@@ -1,3 +1,4 @@
+from .__version__ import __version__ as crawl4ai_version
 import os
 import sys
 import time
@@ -10,7 +11,7 @@ import asyncio
 
 # from contextlib import nullcontext, asynccontextmanager
 from contextlib import asynccontextmanager
-from .models import CrawlResult, MarkdownGenerationResult, CrawlerTaskResult, DispatchResult
+from .models import CrawlResult, MarkdownGenerationResult,DispatchResult
 from .async_database import async_db_manager
 from .chunking_strategy import *  # noqa: F403
 from .chunking_strategy import RegexChunking, ChunkingStrategy, IdentityChunking
@@ -43,8 +44,7 @@ from .utils import (
     RobotsParser,
 )
 
-from typing import Union, AsyncGenerator, List, TypeVar
-from collections.abc import AsyncGenerator
+from typing import Union, AsyncGenerator, TypeVar
 
 CrawlResultT = TypeVar('CrawlResultT', bound=CrawlResult)
 RunManyReturn = Union[List[CrawlResultT], AsyncGenerator[CrawlResultT, None]]
@@ -55,7 +55,7 @@ DeepCrawlManyReturn = Union[
     AsyncGenerator[CrawlResultT, None],
 ]
 
-from .__version__ import __version__ as crawl4ai_version
+
 
 
 class AsyncWebCrawler:
@@ -768,18 +768,19 @@ class AsyncWebCrawler:
                 ),
             )
 
-        transform_result = lambda task_result: (
-            setattr(task_result.result, 'dispatch_result', 
-                DispatchResult(
-                    task_id=task_result.task_id,
-                    memory_usage=task_result.memory_usage,
-                    peak_memory=task_result.peak_memory,
-                    start_time=task_result.start_time,
-                    end_time=task_result.end_time,
-                    error_message=task_result.error_message,
+        def transform_result(task_result):
+            return (
+                    setattr(task_result.result, 'dispatch_result', 
+                        DispatchResult(
+                            task_id=task_result.task_id,
+                            memory_usage=task_result.memory_usage,
+                            peak_memory=task_result.peak_memory,
+                            start_time=task_result.start_time,
+                            end_time=task_result.end_time,
+                            error_message=task_result.error_message,
+                        )
+                    ) or task_result.result
                 )
-            ) or task_result.result
-        )
 
         stream = config.stream