Foreman: low-privilege users can mint access tokens for other accounts

A flaw was found in Foreman’s Api::V2::PersonalAccessTokensController, where Foreman::Controller::UserAware#find_user resolves the target account using User.find(params[:user_id]) without applying the required parent-user authorization check. An attacker with the create_personal_access_tokens permission can therefore invoke POST /api/v2/users/:user_id/personal_access_tokens with another user’s ID and create a Personal Access Token on their behalf. The resulting plaintext token is returned in the API response, while PersonalAccessToken#check_permissions_after_save only validates create_personal_access_tokens on the token and does not enforce edit_users authorization on the target user. The attacker can then use the forged token to authenticate as the victim, potentially resulting in complete account takeover, including administrator accounts.