[Draft] feat: Handle malware sources with many matches

[mhuth]

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Part enhancement but mostly corrects an issue. If a source has many rule matches then its possible its a rogue rules file, ie its not in the usual location we download it to. In that case we ignore its matches so its not reported back to the backend. Hmm, or perhaps we want to keep this so there is a record of rogue rules files :thinking: ...