[general-purpose] Add test assertion helper

[sylvansys]

Parent Issue: #311
Agent Type: general-purpose
Branch: 311-fix/can-u-test-out-the-gh-orchestration-plug

---

Task Description

Add test assertion helper

Task Prompt

Add a second function to plugins/github-orchestration/tests/utils/test-helpers.ts:

export function assertTestPassed(condition: boolean, testName: string): void {
  if (!condition) {
    throw new Error(`Test failed: ${testName}`);
  }
  console.log(formatTestResult(true, testName));
}

This function should use the existing formatTestResult function. Just add this one function to the file.