chore(content-explorer): migrate to TS and replace Enzyme with RTL

[devin-ai-integration]

TypeScript Migration and Test Updates for Content Explorer

This PR migrates the ContentExplorer component from Flow to TypeScript while maintaining Flow compatibility through .js.flow files. It also updates the tests to use React Testing Library instead of Enzyme.

Changes

• Converted ContentExplorer.js to TypeScript (ContentExplorer.tsx)
• Created ContentExplorer.js.flow for Flow compatibility
• Migrated Enzyme tests to React Testing Library
• Added comprehensive type definitions
• Updated internationalization message handling
• Added detailed descriptions for FormattedMessage components

Testing

• All unit tests passing
• Verified component functionality in both list and grid views
• Confirmed internationalization works correctly
• Tested folder navigation and file operations

Link to Devin run: https://app.devin.ai/sessions/c1263916125e435899bc6103146dd98a

[devin-ai-integration]

🤖 Devin AI Engineer

I'll be helping with this pull request! Here's what you should know:

✅ I will automatically:

• Address comments on this PR. Add "(aside)" to your comment to have me ignore it.
• Look at CI failures and help fix them

⚙️ Control Options:

• Disable automatic comment and CI monitoring