praisonai-platform: Any workspace member can promote themselves (or any other member) to owner via PATCH /workspaces/{id}/members/{user_id}

PraisonAI Platform is the platform layer for the PraisonAI multi-agent teams system. Versions prior to 0.1.4 are vulnerable to vertical privilege escalation. The `PATCH /workspaces/{workspace_id}/members/{user_id}` endpoint is gated by `require_workspace_member(workspace_id)`, which defaults to `min_role="member"` and is never overridden by the route. The handler then calls `MemberService.update_role(workspace_id, user_id, body.role)` which sets the target member's role to whatever the request body specifies, with no check that the caller has owner-or-admin privilege, no check that the new role is not higher than the caller's own, and no check that the caller is not silently promoting themselves. PraisonAI Platform version 0.1.4 patches the issue.