chore(09-01): install node-forge + Vitest runner for @tessera/api

- Add node-forge@^1.4.0 runtime dependency (certificate crypto)
- Add @types/node-forge@^1.3.14 and vitest@^3 dev dependencies
- Create apps/api/vitest.config.ts (environment: node, passWithNoTests)
- Add test + test:watch scripts to apps/api/package.json

apps/api/vitest.config.ts

@@ -0,0 +1,10 @@
+import { defineConfig } from 'vitest/config';
+
+export default defineConfig({
+  test: {
+    environment: 'node',
+    globals: true,
+    include: ['src/**/*.spec.ts'],
+    passWithNoTests: true,
+  },
+});