fix(qenv): replace smartfile-based config loading with native fs and yaml parsing for env files

test/test.falsy.ts

@@ -88,7 +88,8 @@ tap.test('should throw error for undefined in strict mode', async () => {
     await testQenv.getEnvVarOnDemandStrict('NON_EXISTENT_VAR');
   } catch (error) {
     threwError = true;
-    expect(error.message).toContain('is not set');
+    const errorMessage = error instanceof Error ? error.message : String(error);
+    expect(errorMessage).toContain('is not set');
   }
   expect(threwError).toBeTrue();
   
@@ -116,4 +117,4 @@ tap.test('should handle array of env vars with falsy values', async () => {
   delete process.env['SECOND_VAR'];
 });
 
-export default tap.start();
+export default tap.start();