refactor(types): migrate enum to const assertion with type inference (WIP)

[coding-ice]

resolve: https://github.com/langgenius/dify/issues/27998

Summary

Could you please review whether this approach is reasonable? If so, I'll proceed with the complete refactoring, as this is a substantial project.

Checklist

• [ ] This change requires a documentation update, included: Dify Document
• [x] I understand that this PR may be closed in case there was no previous discussion or issues. (This doesn't apply to typos!)
• [x] I've added a test for each change that was introduced, and I tried as much as possible to make a single atomic change.
• [x] I've updated the documentation accordingly.
• [x] I ran dev/reformat(backend) and cd web && npx lint-staged(frontend) to appease the lint gods

[gemini-code-assist[bot]]

Summary of Changes

Hello @coding-ice, I'm Gemini Code Assist[^1]! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request begins a strategic refactoring of type definitions within the frontend codebase. It specifically targets the MediaType enum, converting it to a const assertion object to improve type inference and align with modern TypeScript practices. The author is seeking early feedback on this approach before extending the refactoring to other parts of the project, aiming for a more robust and maintainable type system.

Highlights

• Type Refactoring: The MediaType enum in web/hooks/use-breakpoints.ts has been refactored into a const assertion object named mediaTypeMap. This change allows for more precise type inference and potentially better performance or bundle size optimization in TypeScript.
• Consistent Usage Update: All instances where MediaType enum members (e.g., MediaType.mobile, MediaType.pc) were used across various UI components have been updated to reference the new mediaTypeMap object (e.g., mediaTypeMap.mobile, mediaTypeMap.pc). This ensures consistency with the new type definition.
• New Utility Types: Two new utility types, ObjectKeys and ObjectValues, have been introduced in web/types/type.d.ts. These types provide enhanced type safety when working with object keys and values, which can be beneficial for future type-driven refactoring.

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[coding-ice]

@crazywoola CC 🙏