Thunders now handles JS dialogs

Flows that include native browser popups (alerts, confirms, prompts) used to break silently. Not anymore.

• Alert, confirm, and prompt dialogs are now fully supported during test execution.
• Thunders detects and handles JS dialogs triggered from any step, automatically.

If your app uses window.alert(), confirm(), or prompt(), Thunders will interact with those dialogs as part of the test flow. No workaround needed.

#Sprint26