feat: suspend instance improvements (#13861)

* feat(backend): dead instance detection

* feat(backend): suspend type detection

* feat(frontend): show suspend reason on frontend

* feat(backend): resume federation automatically if the server is automatically suspended

* docs(changelog): 配信停止まわりの改善

* lint: fix lint errors

* Update packages/frontend/src/pages/instance-info.vue

* lint: fix lint error

* chore: suspendedState => suspensionState

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Co-authored-by: syuilo <4439005+syuilo@users.noreply.github.com>