Promise Chain to Async/Await Migration

Convert this promise-based code to async/await:

```
[PASTE_PROMISE_CHAIN_CODE]
```

Requirements:
1. **Direct conversion** — maintain identical behavior and error handling
2. **Error handling** — convert .catch() to try/catch, preserve error types
3. **Parallel operations** — use Promise.all() where promises are independent
4. **Sequential operations** — use await for dependent operations
5. **Error propagation** — ensure errors bubble up the same way
6. **TypeScript types** — add return types to async functions
7. **Edge cases** — handle Promise.race, Promise.allSettled if present

Show before/after with comments explaining each transformation.
Flag any behavior changes that the conversion might introduce.