Add team membership management documentation

- Document how team membership is managed through Fedora Accounts groups
- Explain why Forgejo UI team management is not used
- Provide step-by-step instructions for managing team membership
- Include important note about logout/login requirement for changes
- Add to User Documentation navigation

modules/ROOT/nav.adoc

@@ -2,6 +2,7 @@
  ** xref:create_org_profile_page.adoc[How to create an Organization Front Page]
  ** xref:requesting_new_org_or_team.adoc[Requesting a New Organization and/or Team]
  ** xref:organizations_and_teams_mapping.adoc[Organizations and Teams Mapping]
+ ** xref:team_permissions_management.adoc[Team Membership Management with Fedora Accounts]
  ** xref:using_http_auth.adoc[How to Clone a Repo with HTTPS]
  ** xref:issue_pull_request_templates.adoc[Issue and Pull Request Templates]
  ** xref:migration/pagure.adoc[Migrating from Pagure]

modules/ROOT/pages/team_permissions_management.adoc

@@ -0,0 +1,61 @@
+= Team Membership Management with Fedora Accounts
+
+[WARNING]
+====
+**DRAFT DOCUMENTATION:** This documentation is currently in draft form and may not be fully tested and correct. Please verify all procedures before use and report any issues or inaccuracies.
+====
+
+== Overview
+
+This document explains how team membership is managed on Fedora Forge through Fedora Accounts (FAS) groups, and why we don't use Forgejo's built-in team management interface. Understanding this system is crucial for administrators and team members who need to manage team membership and access to repositories and organizations.
+
+== How Team Membership Works
+
+=== Fedora Accounts Integration
+
+Team membership on Fedora Forge is managed exclusively through Fedora Accounts groups. This means:
+
+* **No Direct UI Management**: You cannot add or remove team members directly through the Forgejo web interface
+* **FAS Group Control**: All team membership changes must be made in the corresponding Fedora Accounts group
+* **Automatic Synchronization**: Changes to FAS group membership are automatically reflected in Forgejo team permissions. Users may need to log out and log back into Fedora Forge to see the changes take effect.
+
+
+== How to Manage Team Membership
+
+[IMPORTANT]
+====
+After making changes to FAS group membership, users may need to log out and log back into Fedora Forge to see the changes take effect. The synchronization happens automatically, but the user's session may need to be refreshed to reflect the new team membership.
+====
+
+=== Adding Team Members
+
+To add someone to a team:
+
+. Log into `accounts.fedoraproject.org`
+. Navigate to the appropriate FAS group (e.g., `forge-rust-members`)
+. Add the user to the group
+. The user will automatically gain access to the corresponding Forgejo team
+
+=== Removing Team Members
+
+To remove someone from a team:
+
+. Log into `accounts.fedoraproject.org`
+. Navigate to the appropriate FAS group
+. Remove the user from the group
+. The user will automatically lose access to the corresponding Forgejo team
+
+=== Changing Team Membership
+
+To change someone's team membership:
+
+. Remove them from their current FAS group
+. Add them to the FAS group corresponding to the new team
+. The change will be reflected automatically in Forgejo
+
+== Related Documentation
+
+* xref:fas_group_naming_standards.adoc[FAS Group Naming Standards]
+* xref:organizations_and_teams_mapping.adoc[Organizations and Teams Mapping]
+* xref:creating_a_new_team.adoc[Creating a New Team]
+* xref:requesting_new_org_or_team.adoc[Requesting New Organizations/Teams]