telemetry preference validation skips falsy non-boolean values and runs after telemetry init

### Summary

`validatePreferences()` only validates `preference.telemetry` inside a truthiness check, so falsy non-boolean values such as `0` are accepted without throwing. Separately, `createBaseAccountSDK()` initializes telemetry before it calls `validatePreferences()`, so invalid telemetry preferences can be acted on before validation runs.

### Why this matters

The documented opt-out value is `preference: { telemetry: false }`. If a caller accidentally passes a falsy non-boolean value such as `0`, the SDK currently does not reject it during preference validation. Since the runtime check uses strict comparison (`telemetry !== false`), `0` is treated as not opted out and telemetry remains enabled.

### Code paths

`packages/account-sdk/src/util/validatePreferences.ts`:

```ts
if (preference.telemetry) {
if (typeof preference.telemetry !== 'boolean') {
throw new Error(`Telemetry must be a boolean`);
}
}
```

`packages/account-sdk/src/interface/builder/core/createBaseAccountSDK.ts` initializes telemetry before validating preferences.

### Expected behavior

Preference validation should reject any defined non-boolean `telemetry` value, including falsy values like `0`, before telemetry initialization logic can use it.

Read packages/account-sdk/src/util/validatePreferences.ts and packages/account-sdk/src/interface/builder/core/createBaseAccountSDK.ts first. Trace preference validation and telemetry initialization in that entry point; done means every defined non-boolean telemetry value, including 0, is rejected before telemetry initialization can use it.

Written by the indexing model from the issue text.