feat(useFileDialog): add directory parameters

[huiliangShen]

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⚠️ Slowing down new functions

Warning: Slowing down new functions

As the VueUse audience continues to grow, we have been inundated with an overwhelming number of feature requests and pull requests. As a result, maintaining the project has become increasingly challenging and has stretched our capacity to its limits. As such, in the near future, we may need to slow down our acceptance of new features and prioritize the stability and quality of existing functions. Please note that new features for VueUse may not be accepted at this time. If you have any new ideas, we suggest that you first incorporate them into your own codebase, iterate on them to suit your needs, and assess their generalizability. If you strongly believe that your ideas are beneficial to the community, you may submit a pull request along with your use cases, and we would be happy to review and discuss them. Thank you for your understanding.

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Description

• add directory parameter to select a whole directory
• adapt to useFileDialog: enable uploading a directory instead of files #3441

Additional context

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🤖 Generated by Copilot at 262a1aa

This pull request adds a new feature to the useFileDialog hook that enables directory selection in some browsers. It also updates the documentation with an example of using this feature.

🤖 Generated by Copilot at 262a1aa

• Add directory option to useFileDialog hook to enable selecting directories in the file dialog (link, link, link, link)
• Update the UseFileDialogOptions interface and the DEFAULT_OPTIONS constant to include the directory option, which is a boolean that defaults to false (link, link)
• Set the webkitdirectory attribute of the input element to the value of the directory option, using a non-standard feature that works in some browsers (link)
• Add an example of using the directory option in the documentation file index.md (link)

[JakobMiksch]

Code looks fine and it works well!
Would be great to merge this soon :-)