chore: Replace markdown issue templates with forms

[phated]

Related issue(s)

Resolves #

Description

This switches our markdown issue templates into GitHub Issue Forms. I like these issue forms because we can provide a lot of extra information to submitters that isn't leaked into the issue body, and we don't need to use comments.

You can test the organization-wide generic ones at https://github.com/noir-lang/aztec_backend/issues/new?assignees=&labels=bug&template=bug_report.yml and these will also render as forms if you look at the markdown directly on my branch (not in the diff).

I've kept these templates in the repository and updated them because they capture more specific information about the environment. When you override a single issue template in the repository, you need to provide them all, so the feature_request.yml is the same as the company wide one.

Copying @Globallager since he last made updates to the environment section.

Summary of changes

Dependency additions / changes

Test additions / changes

Checklist

• I have tested the changes locally.
• I have formatted the changes with Prettier and/or cargo fmt with default settings.
• I have linked this PR to the issue(s) that it resolves.
• I have reviewed the changes on GitHub, line by line.
• I have ensured all changes are covered in the description.
• This PR requires documentation updates when merged.

Additional context