test(cli): add crypto roundtrip and invite parse tests

Cover encryptDirect/decryptDirect with three scenarios (happy path,
wrong recipient, tampered ciphertext) and invite link parsing with
round-trip, expiry rejection, and malformed input handling.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/cli/vitest.config.ts

@@ -0,0 +1,7 @@
+import { defineConfig } from "vitest/config";
+
+export default defineConfig({
+  test: {
+    include: ["src/__tests__/**/*.test.ts"],
+  },
+});