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/tsconfig.json

@@ -0,0 +1,10 @@
+{
+  "extends": "../../tsconfig.base.json",
+  "compilerOptions": {
+    "outDir": "./dist",
+    "rootDir": "./src",
+    "types": ["node"]
+  },
+  "include": ["src/**/*.ts"],
+  "exclude": ["src/**/*.test.ts", "src/**/*.spec.ts"]
+}