Show more actionable message when user has no project permissions instead of "Oops" #6723
Description
Is your feature request related to a problem?
Summary
When a user is added to an organisation but has no project-level permissions, the UI displays a generic "Oops" error. This should instead show a meaningful message indicating they don't have access to any projects and should contact their org admin.
Current Behavior
A user who successfully joins an organisation but has not been granted access to any projects sees a generic "Oops" page with no explanation.
Describe the solution you'd like.
The UI should detect that the user has org membership but no project permissions, and display a message like "You don't have access to any projects yet. Contact your organisation admin to get access."
Describe alternatives you've considered
Don't show an error at all. Show the dashboard with an empty state like "No projects available contact your admin for access."
Additional context
Edge cases to address:
- Organizations with no projects at all
- Don't show the "contact administrator" message to organization admins themselves (since they are the administrators)