Api endpoint with public and group deploy keys
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We iterated https://gitlab.com/gitlab-org/gitlab/-/issues/28766 with the API endpoint solution https://docs.gitlab.com/ee/api/deploy_keys.html#list-project-deploy-keys-for-user.
While this should solve most of the requirement definition as perceived from the original issue
> If a maintainer/owner wants to automate the enabling of deploy keys for a bunch of projects, they have to be either an administrator or call an administrator to get the id of the particular key they need (because [list-project-deploy-keys](https://docs.gitlab.com/ee/api/deploy_keys.html#list-project-deploy-keys) API lists only those keys which are enabled on the given project). If the maintainer/owner have an api endpoint on which they can find all the keys accessible by them, they could full-fill their task without further inconvenience.
A precise solution will be to include [public deploy keys](https://docs.gitlab.com/ee/user/project/deploy_keys/index.html#scope) in addition to project deploy keys. And if required by the customers we can consider to include [group deploy deploy](https://gitlab.com/gitlab-org/gitlab/-/issues/14729) keys in addition to the public deploy keys.
Creating this issue to understand the customers requirements and capture additional/missing details.
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