Complete the new version of the Spec

Problem: The scope the of next specification release is distributed among different issues and PRs. Some of the items have been included in milestones but not all what makes it difficult to progress with the release discussions. By identifying the pending scope and applying some project management to support the progress we hope to lighten the whole process.

Team working on this issue:

• @benjagm to project manage this work.
• @jdesrosiers and @gregdennis to write up list of work the believe still needs to be done.

Assessed as high impact/high effort during our collaborators summit 2023.

Updated plan:

• We'll create a new milestone called stable-release. We'll create a project board to enhance collaboration and transparency.
  Milestone: https://github.com/json-schema-org/json-schema-spec/milestone/10
  Project Board: https://github.com/orgs/json-schema-org/projects/15/views/1
• We'll conduct a grooming session to setup the initial spec backlog associating the issues with the new milestone.
• We'll decide if we remove the existing milestones.
• We'll decide a labelling system to identify the issues' workflow. Before, during and after an issue is added to the spec scope.
• We'll run 1 week cycles to decide the issues to focus on during that cycle. 1 session at the beginning to decide scope of the cycle and 1 session at the end to review the closed issues, and decide the issues for the next cycle. Short cycles can be done in during the OCWM.