Change all account actions except "none" to resolve all unresolved reports

Refactor `SuspendAccountService` to be more readable

- Some associations were missing from the clean-up
- Some attributes were not reset on suspension
- Skip federation and streaming deletes when purging a dead domain
- Move account association definitions to concern

Fix #5597

* Add form for account deletion

* If avatar or header are gone from source, remove them

* Add option to have SuspendAccountService remove user record, add tests

* Exclude suspended accounts from search