docs: add developer readme

[aorinevo]

Background

While we have a Developer guide published here (link), there are some recent changes that are not captured and worth having readily accessible within the repo.

This pull request adds a comprehensive developer guide for WeBWorK in the new DEVELOPER.md file. The guide covers the tech stack, setup instructions for both Docker and native development, project structure, architecture overview, frontend development, configuration conventions, code style and linting, useful scripts, contribution guidelines, and troubleshooting tips. This documentation aims to make onboarding and development much easier for new contributors.

Key additions in developer documentation:

• Added a detailed overview of the tech stack, listing backend, frontend, database, job queue, math rendering, deployment, and problem generation technologies.
• Provided step-by-step instructions for local development setup using both Docker and native environments, including configuration, asset building, and course creation.
• Documented the project directory structure and explained the architecture, including the application entry point, ContentGenerator pattern, and database layer.
• Included frontend development instructions, configuration file conventions, code style and linting guidelines, and a table of useful scripts for common tasks.
• Added troubleshooting guidance for common development issues such as asset loading, Docker volume errors, and two-factor authentication prompts.

[drgrice1]

First, please target this pull request to the develop branch. All pull requests go there except for hotfix pull requests, and this does not qualify for that.

This will most likely need a discussion by the development team. Some of the things mentioned (like the dependencies) will require a lot of maintenance to keep this page up to date. Which might not be desirable.

Note that jQuery is not a dependency of WeBWorK 2 at all, and should be removed at the very least from the "Tech Stack" section. It is provided for PG problems for legacy reasons, but should not actually be used by those. It is certainly not a "key" dependency.

[aorinevo]

Hi @drgrice1 - I hope all is well and appreciate the quick response. Will update to target develop branch and understand that this will need discussion by the development team.

[drgrice1]

You are probably going to need to cherry pick your commit onto the develop branch or rebase onto develop and drop unrelated commits so that the hotfix pull requests to main are not brought along.

[drgrice1]

I find an interactive rebase easiest for this. Just do git rebase -i origin/develop, and then change "pick" to "drop" for all but this commit.

[drgrice1]

It seems you have it now!

[aorinevo]

I opted for force push:

1. add upstream
2. set branch to track upstream develop
3. reset HEAD~1
4. stash changes
5. reset --hard upstream/develop
6. git stash pop
7. commit
8. push local:remote --force