Categorisation rules

Tell Holstead how to tag transactions automatically. Each rule has conditions (description contains, counterparty equals, amount greater than, etc) and effects (set category, mark intra-group, tag entity). Rules run when you record a manual transaction; batch-apply re-runs them over rows you've already added. Phase 4 reuses the same rules at bank-feed ingest, so the work you do here pays off the moment Basiq lands.