## Summary
This PR introduces comprehensive event waiting utilities for both
DataHaven (Substrate) and Ethereum chains, providing a unified
interface for handling blockchain events in E2E tests.
## What's New
- **Event Utilities** (`test/utils/events.ts`): New utilities for
waiting on blockchain events
- `waitForDataHavenEvent`: Type-safe event waiting for Substrate chain
events
- `waitForEthereumEvent`: Event waiting for Ethereum contract events
- Graceful timeout handling (returns null instead of throwing)
- Support for event filtering, callbacks, and custom timeouts
- **Documentation** (`test/docs/event-utilities-guide.md`):
Comprehensive guide covering usage examples for both DataHaven and
Ethereum.
## Test Plan
- [ ] New event utilities work as expected
- [ ] Event filtering works correctly for both chains
- [ ] Timeout handling behaves as documented
- [ ] Parallel event waiting with `Promise.all()` works
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Co-authored-by: Claude <noreply@anthropic.com>
