CRM / campaigns / enrichment: minor cleanup & test-coverage backlog

[pdovhomilja]

Consolidated minor follow-ups deferred during recent CRM/campaign/enrichment work. None is user-impacting on its own; grouped for tracking. Split any item out if picked up.

Data integrity / correctness

• Contacts: account existence / soft-delete not validated before linking contact.accountsIDs; no test for the accountsIDs-set-but-zero-open-opps branch.
• Enrichment idempotency: TOCTOU race on the idempotency check (findFirst + create not transactional; currently best-effort de-dup).
• import-targets: emails array not deduped before findMany; suppression assignments on valid: any[] are not type-checked (pre-existing any).

Cleanup

• actions/crm/products/import-products.ts is still Papa-only — candidate for the shared CSV parser.
• Delivery-deadline picker reuses closeDatePlaceholder copy — add a dedicated i18n key.
• Seed: add a comment rationale for the "Signing" → purchase_order mapping.

Test coverage

• No automated test for updateOpportunity delivery_deadline (create path covered only).
• Campaign send: failure-path test doesn't assert console.error was called, nor that the per-send DB update happened first.
• Line-item wrapper tests assert the parent findFirst was called, but not that it was called with the resolved parent id.