add Crawl4AI to tools and for sync data from website in Knowledge

[chankwongyin]

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1. Is this request related to a challenge you're experiencing? Tell me about your story.

I found from Crawl4AI who states that they outperforms Firecrawl significantly:

Simple crawl: Crawl4AI is over 4 times faster than Firecrawl. With JavaScript execution: Even when executing JavaScript to load more content (doubling the number of images found), Crawl4AI is still faster than Firecrawl's simple crawl.

I would suggest to add this tool to dify to allow different ways to crawl the data from websites.

2. Additional context or comments

No response

3. Can you help us with this feature?

• [ ] I am interested in contributing to this feature.

[chankwongyin]

For your convenience: https://github.com/unclecode/crawl4ai