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>

vitest.config.ts

@@ -0,0 +1,18 @@
+import { defineConfig } from 'vitest/config';
+import { fileURLToPath } from 'node:url';
+
+const r = (p: string) => fileURLToPath(new URL(p, import.meta.url));
+
+export default defineConfig({
+  resolve: {
+    alias: {
+      // Resolve workspace packages to their TS source so tests run without a
+      // build step. Production builds still go through tsc/dist.
+      '@insignia/iios-contracts': r('./packages/iios-contracts/src/index.ts'),
+      '@insignia/iios-testkit': r('./packages/iios-testkit/src/index.ts'),
+    },
+  },
+  test: {
+    include: ['packages/**/src/**/*.{test,spec}.ts'],
+  },
+});