Create Concept Architects and Release Discipline

Why is this change being made?

This merge request adds two new handbook pages for the Concept Architects team within GitLab's Design Strategy group.

The first page introduces the Concept Architects team — explaining that they focus on the long-term future of GitLab's product experience by developing well-researched design concepts to guide executive investment decisions, rather than working on day-to-day features or existing roadmaps.

The second page establishes a Concept Release Discipline — a structured process governing how and when concept work is shared. It defines three release phases (dark, internal debut, and external), clarifies who is responsible for moving work between phases, sets expectations for which communication channels to use at each stage, and outlines how external collaborators should be brought into early-stage work without prematurely exposing concepts to broader audiences.

Related: gitlab-com/designops#21, https://gitlab.com/gitlab-org/design-strategy/concept-architects/-/work_items/14

Author and Reviewer Checklist

Please verify the check list and ensure to tick them off before the MR is merged.

• Provided a concise title for this Merge Request (MR)
• Added a description to this MR explaining the reasons for the proposed change, per say why, not just what
  • Copy/paste the Slack conversation to document it for later, or upload screenshots. Verify that no confidential data is added, and the content is SAFE
• Assign reviewers for this MR to the correct
  • The when to get approval handbook section explains when DRI approval is required
  • The who can approve handbook section explains how to identify the DRI
  • If the MR does not require DRI approval, consider asking someone on your team, such as your manager.
  • The approver may merge the MR. If they approve but don't merge, you can merge.
• For transparency, share this MR with the audience that will be impacted.
  • Team: For changes that affect your direct team, share in your group Slack channel
  • Department: If the update affects your department, share the MR in your department Slack channel
  • Division: If the update affects your division, share the MR in your division Slack channel
  • Company: If the update affects all (or the majority of) GitLab team members, post an update in #whats-happening-at-gitlab linking to this MR
    • For high-priority company-wide announcements work with the internal communications team to post the update in #company-fyi and align on a plan to circulate in additional channels like the "While You Were Iterating" Newsletter

Commits

• Create Concept Architects and Release Discipline

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