Backend: Rename CI classes to better reflect CI domain
## Proposal * Rename `CommitStatus` to `Ci::Job` * Rename `GenericCommitStatus` to `Ci::StaticJob` ( `Ci::ProxyJob`, `Ci::GenericJob` are alternatives) - We are calling this `Static` in that it isn't processed by a gitlab runner or triggering a downstream, but these can actually have associated tasks in gitlab such as a deployment of the 'pages' feature. It's more that they are agnostic to what processing is performed and just represent the status of some processing happening somewhere (not on a runner). `Ci::ProxyJob`, `Ci::GenericJob` are alternatives ## Full organization after rename * `CommitStatus` =\> `Ci::Job` * `GenericCommitStatus < CommitStatus` =becomes=> `Ci::StaticJob < Ci::Job` ( * `Ci::Processable < CommitStatus` =becomes=> `Ci::ProcessableJob < Ci::Job` * `Ci::Build < Ci::Processable` =becomes=> `Ci::ExecutableJob < Ci::ProcessableJob` * `Ci::Bridge < Ci::Processable` =becomes=> `Ci::TriggerJob < Ci::ProcessableJob` Relations for `Ci::Pipeline`; * `has_many :jobs` for all * `has_many :processable_jobs` for `Ci::ExecutableJob` and `Ci::TriggerJob`
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