🎩 What? Why?

Some NPM packages used by the project are very old. This could affect the project maintenaince and security, as it's not possible to update packages with recent versions. This PR tries to improve that.

These are the main issues found:

• The graphql-docs npm package is very old and it's not maintained. I've tried to update it but it requires too much work to do it. I've found a gem also called graphql-docs that generates a very similar output but statically. I've created a rake task that uses it and generates those static files in the app/views/static/ folder. Then, I've embeded those files into the docs view, to get a result very similar to the existing solution. The task can be run manually, but it will be run after the creation of the app and after each decidim upgrade. The only "problem" is that this static files should be added to the app repository, and that's a bit ugly.
• The leaflet-svgicon package has a strange dependency from the src package that seems not to be used. This package was not created by the original code writer. I've created a fork from that repository and published it as a package called @decidim/leaflet-svgicon.

📌 Related Issues

• Related to Remove npm decidim packages with dependencies from other decidim packages #8330

Testing

Describe the best way to test or validate your PR.

📋 Checklist

🚨 Please review the guidelines for contributing to this repository.

• ❓ CONSIDER adding a unit test if your PR resolves an issue.
• ✔️ DO check open PR's to avoid duplicates.
• ✔️ DO keep pull requests small so they can be easily reviewed.
• ✔️ DO build locally before pushing.
• ✔️ DO make sure tests pass.
• ✔️ DO make sure any new changes are documented in docs/.
• ✔️ DO add and modify seeds if necessary.
• ✔️ DO add CHANGELOG upgrade notes if required.
• ✔️ DO add to GraphQL API if there are new public fields.
• ✔️ DO add link to MetaDecidim if it's a new feature.
• ❌AVOID breaking the continuous integration build.
• ❌AVOID making significant changes to the overall architecture.

📷 Screenshots

Please add screenshots of the changes you're proposing

♥️ Thank you!