feature: add new free courses in JavaScript (Astro, Electron, React)

[HRIDYANSHU054]

What does this PR do?

Add resource(s)

IMPORTANT

• Read our contributing guidelines.
• Is this a revision of a previously submitted PR? If so, STOP! Go back, reopen the PR, and add commit(s) the branch you previously submitted. Please don't make the job of reviewing more difficult by hiding previous work.

For resources

Description

Adding three free, full-length video courses/tutorials to the JavaScript section. The courses cover modern frameworks and technologies:

1. Astro
2. Electron Course - Code Desktop Applications (inc. React and Typescript)
3. React Tutorial Full Course - Beginner to Pro (React 19, 2025)

Why is this valuable (or not)?

These resources are valuable as they cover high-demand modern JavaScript frameworks (React, Astro) and a popular desktop application framework (Electron), offering comprehensive, long-form tutorials.

How do we know it's really free?

All courses are freely available as videos on YouTube.

For book lists, is it a book? For course lists, is it a course? etc.

These are free online video courses/tutorials.

Checklist:

• Search for duplicates.
• Include author(s) and platform where appropriate.
• Put lists in alphabetical order, correct spacing.
• Add needed indications (PDF, access notes, under construction).
• Used an informative name for this pull request.

Follow-up

• Check the status of GitHub Actions and resolve any reported warnings!

[eshellman]

For youtube, we prefer "playlist" links and the name of the producer/creator. docs/CONTRIBUTING.md#platforms-and-access-notes

[HRIDYANSHU054]

Electron Course - Code Desktop Applications (inc. React and Typescript)

• freeCodeCamp.org

React Tutorial Full Course - Beginner to Pro (React 19, 2025)

• SuperSimpleDev

Although these are standalone videos rather than playlists, they are comprehensive and self-contained, covering nearly all the material you would find in a multi-video course.
The Electron course is around 3 hours, and the React course is 11 hours, making them full-length, structured tutorials suitable for inclusion.