Bug: README code examples missing await on provider.request() calls

### Describe the bug

Two code examples in the README are missing `await` on `provider.request()` calls, which would cause unexpected behavior for anyone copying the examples.

### Steps

1. See README.md lines 176 and 184
2. const addresses = provider.request({ method: 'eth_requestAccounts' });
3. provider.request('personal_sign', [...]);

### Expected behavior

Both calls should have await since provider.request() returns a Promise:

const addresses = await provider.request({ method: 'eth_requestAccounts' });
await provider.request('personal_sign', [...]);

### Version

latest

### Additional info

_No response_

### Desktop

_No response_

### Smartphone

_No response_

Open README.md at lines 176 and 184 and review the two provider.request() examples. Add await to both calls, then verify the examples show the expected Promise-handling behavior.

Written by the indexing model from the issue text.