fix(docker): resolve filter serialization and JSON encoding errors in deep crawl strategy

[ntohidi]

Summary

Fixed Docker server filter serialization and JSON encoding errors when using deep crawl strategies with filter chains. The server was returning 500 errors when FilterChain was specified in BFSDeepCrawlStrategy, and filters were not being properly applied during crawling.

Fixed DeepCrawlStrategy fails with AttributeError when max_pages limit is reached in Docker mode.

Fixed Deep crawl fails in the Docker environment because Logger objects are converted into dictionaries.

Fixes #1419, #1437, #1357

List of files changed and why

• crawl4ai/async_configs.py - Removed serialization of private slots attributes that were incorrectly being passed as constructor parameters during deserialization
• crawl4ai/deep_crawling/filters.py - Added public attributes to URLPatternFilter to store original constructor parameters for proper serialization/deserialization
• crawl4ai/models.py - Fixed model_dump() to handle property descriptors that were causing "Object of type property is not JSON serializable" errors

How Has This Been Tested?

Tested with a comprehensive test suite covering:

1. Docker Client Test: Verified that Crawl4aiDockerClient can successfully serialize and send filter chains to the server without TypeErrors
2. REST API Test: Confirmed that direct REST API calls with filter chain payloads work correctly
3. Round-trip Serialization: Ensured filter chains maintain all properties through serialization/deserialization cycle
4. Real URL Filtering: Tested with actual websites (GitHub, Stack Overflow, Python.org, Wikipedia) to verify filters correctly block/allow URLs based on patterns
5. Deep Crawl Execution: Validated that BFSDeepCrawlStrategy with filters successfully crawls and filters URLs (tested with docs.crawl4ai.com, filtering for "core" pattern - correctly returned 21 matching
   URLs)

Test scenarios included:

• Pattern matching with reverse filters (about, privacy, terms)
• Complex filter chains with 13+ patterns
• Max depth and max pages limits
• Both streaming and non-streaming modes

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added/updated unit tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

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