feat(testkit): deterministic fake platform ports + fixtures + replay oracle

Fakes for all 7 IiosPlatformPorts (deny/timeout/ambiguous controls), portal +
unknown-email fixtures, replayTwice idempotency oracle. Adds ingest request
contract. Vitest alias resolves workspace packages to source.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

packages/iios-testkit/src/fixtures/email-from-unknown.ts

@@ -0,0 +1,13 @@
+import type { IngestInteractionRequest } from '@insignia/iios-contracts';
+
+/** An email from an unrecognised address — the handle must stay UNRESOLVED. */
+export const emailFromUnknown: IngestInteractionRequest = {
+  scope: { orgId: 'org_demo', appId: 'portal-demo' },
+  channel: { type: 'EMAIL', externalChannelId: 'support-inbox' },
+  source: { handleKind: 'EMAIL', externalId: 'someone@example.com', displayName: 'Someone' },
+  kind: 'EMAIL',
+  thread: { externalThreadId: 'thr_email_1', subject: 'Question about my plot' },
+  parts: [{ kind: 'TEXT', bodyText: 'Hello, I have a question.' }],
+  occurredAt: '2026-06-30T15:12:00.000Z',
+  providerEventId: 'evt_email_1',
+};