Navigation update - Product Planning request: replaces issue/epic lists with work items

Proposal

We plan to enhance the user experience by consolidating planning views into a unified "Work Items" page. This change will consolidate issues and epics under a single navigation item at both Project and Group levels. With this change we want to streamline navigation within project management workflows by providing a unified view of all work items (longer term), improving user experience.

Proposed Changes

1. Sidebar Navigation Update:
   • Project Level:
     • Replace the "Issues" link with "Work Items."
   • Group Level:
     • Replace both "Issues" and "Epics" links with "Work Items."
   • We will not be introducing a new "count" badge beside the new 'Work Items' nav item.
2. New /work_items Page:
   • Create a new /work_items web route that renders the existing WorkItemListApp without any default type filter.
3. Feature Flag Implementation:
   • Introduce a work_items_planning_view feature flag to control the rollout.
   • When enabled, the sidebar updates to show "Work Items."
   • When disabled, the existing "Issues" and "Epics" links remain unchanged.
4. Redirects:
   • Handle redirecting from existing /issues and /epics routes to /work_items (separate issue with more detail #513115 )

Usage

• Users will access a centralized "Work Items" page for streamlined planning and management.
• The feature flag allows for controlled testing and feedback before full deployment.

Business Drivers

• Improved User Experience:
  • Simplifies navigation by consolidating related items into a single view.
• Enhanced Planning Efficiency:
  • Provides a comprehensive overview of work items, facilitating better project management.
• Controlled Rollout:
  • The feature flag ensures stability and user adaptability during the transition.

These changes are designed to streamline workflows, improve usability, and align with GitLab's commitment to enhancing project planning capabilities.

Other locations that were considered

Since this navigation item is a consolidation or replacement of existing items (not adding a new navigation item), we were not considering a different location. We did consider alternative naming for the navigation item, which were explored in some of the research and analysis below:

• https://gitlab.com/gitlab-org/ux-research/-/issues/3001+
• Mental model study
• Competitive analysis

Designs

Please see SSOT of designs here: #430137[List.png]

Checklist

• Review the handbook page for navigation.
• Add relevant information to the issue description detailing your proposal, including usage and business drivers.
• List at least two other places you considered to introduce your feature.
• Add relevant designs to the Design Management area of the issue.
• Ensure your UI suggestion align with the Documentation Style Guide.
• Engage Technical Writing. They can help craft a term that best describes the feature(s) you’re proposing.
• Follow the product development workflow validation process to ensure you are solving a well understood problem and that the proposed change is understandable and non-disruptive to users. Navigation-specific research is mandatory for additions or when restructuring.
• Engage the Foundations Product Manager for approval. The Foundations DRI (@jtucker_gl) will work with UX partners in product design, research, and technical writing, as applicable.
• Consider whether you need to communicate the change somehow, or if you will have an interim period in the UI where your item will live in more than one place.
• Ensure engineers are familiar with the implementation steps for navigation.