test: add deterministic resilience matrix

vite.config.ts

@@ -2,12 +2,27 @@ import { fileURLToPath, URL } from 'node:url';
 import { defineConfig } from 'vite';
 import vue from '@vitejs/plugin-vue';
 
-export default defineConfig({
-  plugins: [vue()],
-  build: {
-    sourcemap: false,
-  },
-  resolve: {
-    alias: { '@': fileURLToPath(new URL('./src', import.meta.url)) },
-  },
+export default defineConfig(() => {
+  const testBuild = process.env.PORTFOLIO_TEST_BUILD === '1';
+  const testTokenDigest = process.env.PORTFOLIO_TEST_TOKEN_DIGEST ?? '';
+  if (testBuild && !/^[a-f0-9]{64}$/u.test(testTokenDigest)) {
+    throw new Error('Authenticated test builds require one SHA-256 token digest.');
+  }
+  if (!testBuild && testTokenDigest !== '') {
+    throw new Error('A test token digest cannot influence a production build.');
+  }
+
+  return {
+    plugins: [vue()],
+    define: {
+      __PORTFOLIO_TEST_BUILD__: JSON.stringify(testBuild),
+      __PORTFOLIO_TEST_TOKEN_DIGEST__: JSON.stringify(testBuild ? testTokenDigest : ''),
+    },
+    build: {
+      sourcemap: false,
+    },
+    resolve: {
+      alias: { '@': fileURLToPath(new URL('./src', import.meta.url)) },
+    },
+  };
 });