fix(tests): clear GITHUB_ACTIONS env in vitest unit project to prevent auto-invocation on import

Agent-Logs-Url: https://github.com/amondnet/vercel-action/sessions/e840b930-a078-4381-91dc-06dc24402e36

Co-authored-by: amondnet <1964421+amondnet@users.noreply.github.com>

Author: Copilot

src/index.ts

@@ -345,10 +345,11 @@ export async function run(): Promise<void> {
   }
 }
 
-// Auto-invoke run() only inside the GitHub Actions runner. A negative guard
-// like `!process.env.VITEST` would silently disable the action in any
-// workflow that happens to set VITEST (e.g. a step running unit tests in the
-// same job). GITHUB_ACTIONS is the canonical, runner-set sentinel.
+// Auto-invoke run() only inside the GitHub Actions runner.
+// GITHUB_ACTIONS is the canonical, runner-set sentinel that is not
+// user-controllable. Unit tests override this to '' in vitest.config.ts
+// (via test.env) so that module imports during tests do not trigger
+// auto-invocation.
 if (process.env.GITHUB_ACTIONS === 'true') {
   run().catch((error: unknown) => {
     if (error instanceof Error) {

vitest.config.ts

@@ -25,6 +25,10 @@ export default defineConfig({
           exclude: ['node_modules', 'dist', 'example'],
           testTimeout: 10000,
           hookTimeout: 10000,
+          // Prevent index.ts from auto-invoking run() when tests import it.
+          // The guard uses GITHUB_ACTIONS === 'true', which is set to 'true'
+          // in the CI runner environment where unit tests also run.
+          env: { GITHUB_ACTIONS: '' },
         },
       },
       {