test: fix flaky E2E scenarios and stabilize test runner

scripts/test/run-e2e-suite.mjs

@@ -112,7 +112,10 @@ async function main() {
   }
 
   for (const [index, suite] of suites.entries()) {
-    const runEnvironment = suite.useDedicatedDatabase ? { DATABASE_URL: e2eDatabaseUrl, E2E_DATABASE_URL: e2eDatabaseUrl } : {};
+    // E2E_DATABASE_URL is not in .env so pnpm's auto-loading cannot override it.
+    // vitest.config.e2e.ts reads this and injects it as DATABASE_URL into all
+    // test workers, ensuring NestJS never connects to the dev database.
+    const runEnvironment = { E2E_DATABASE_URL: e2eDatabaseUrl };
 
     if (suite.prepareDedicatedDatabase) {
       console.log(`Resetting and migrating dedicated e2e database for suite ${suite.id}...`);
@@ -134,6 +137,8 @@ async function main() {
         "exec",
         "vitest",
         "run",
+        "--config",
+        "vitest.config.e2e.ts",
         suite.vitestTarget,
         "--reporter=default",
         "--reporter=junit",

server/vitest.config.e2e.ts

@@ -0,0 +1,25 @@
+import path from 'path';
+import { defineConfig } from 'vitest/config';
+
+const e2eDatabaseUrl =
+  process.env.E2E_DATABASE_URL ?? 'postgres://projectx:projectx@localhost:5432/projectx_e2e';
+
+export default defineConfig({
+  resolve: {
+    tsconfigPaths: true,
+    alias: {
+      '@projectx/types': path.resolve(__dirname, '../packages/types/src/index.ts'),
+    },
+  },
+  test: {
+    globals: true,
+    environment: 'node',
+    pool: 'forks',
+    include: ['test/**/*.e2e-spec.ts'],
+    passWithNoTests: true,
+    reporters: process.env.CI ? ['default', 'github-actions'] : ['default'],
+    env: {
+      DATABASE_URL: e2eDatabaseUrl,
+    },
+  },
+});