A DSO verzoek with no mapped activity makes no case and reaches nobody (REQ-DSO-013) #3457

What is missing

A DSO verzoek whose activities map to no case type makes no case, and nobody is told.

Why it matters

DsoIntakeCasePayload::payloadFor() throws when no case type answers to the mapping. The verzoek then waits in integriq with activityUnmapped: true, and no handler sees it. Statutory terms can run without anyone knowing.

Where

• lib/Service/Dso/DsoIntakeCasePayload.php:70-75.
• The requirement: integriq openspec/specs/dso-omgevingsloket/spec.md, REQ-DSO-013 (triage case, "Onbekend DSO-activiteit" case type, notify the DSO triage user).

Already done

• integriq flags activityUnmapped and lists unmapped activities for the admin (integriq#2484, integriq#2502).
• Since integriq#2603 and fix(dso): one intake path for a DSO verzoek, complaints on klacht-behandeling #3446, dossiq is the one intake path that makes the case. So the triage case belongs here.

Done when

• An unmapped verzoek opens a triage case on a configured case type, and a configured user or group gets a notification.
• A mixed verzoek (some mapped, some not) opens its mapped cases and one triage case.
• Live proof with one unmapped push is in the PR.