client/modules/Preview: migrate to TypeScript, no-verify

[NalinDalal]

Fixes #3828

Summary

Migrated client/modules/Preview from JavaScript to TypeScript to improve type safety and developer experience.

Changes

Files Converted:

File	Description
EmbedFrame.tsx	Main preview iframe component with styled-components
filesReducer.ts	Redux reducer for managing preview files
previewIndex.tsx	Preview entry point

Type Definitions Added

PreviewFile interface (filesReducer.ts:6-16):

interface PreviewFile {
  id: string;
  name: string;
  content: string;
  url?: string;
  blobUrl?: string;
  children: string[];
  filePath?: string;
  fileType?: string;
  _id?: string;
  isSelectedFile?: boolean;
}

EmbedFrameProps interface (EmbedFrame.tsx:21-27):

interface EmbedFrameProps {
  files: PreviewFile[];
  isPlaying: boolean;
  basePath: string;
  gridOutput: boolean;
  textOutput: boolean;
}

Module Declarations

Added type declarations for third-party libraries (custom.d.ts):

• loop-protect - Loop protection library
• mime - MIME type detection library

Other Changes

• Removed PropTypes runtime validation (replaced with compile-time TypeScript types)
• Added strict typing for all function parameters and return values
• Updated webpack config to resolve .tsx extensions

Breaking Changes

None - all changes are backward compatible.

[release-com]

Release Environments

This Environment is provided by Release, learn more!
To see the status of the Environment click on Environment Status below.

• p5.js-web-editor
  • app-tedd271.release.editor.p5js.org/
  • preview-tedd271.release.editor.p5js.org/

🔧Environment Status : https://app.release.com/public/Processing%20Foundation/env-6e3c605b9c

[yugalkaushik]

While working on the migration to TypeScript, please ensure that all changes are clearly and thoroughly documented in the PR description. This should include details about what was converted, any type definitions added or modified, breaking changes (if any), and the overall approach taken. Clear documentation helps reviewers understand the scope and intent of the changes more effectively.

[NalinDalal]

Updated with correct types and description on pr body