Add `dataCollection` option type and deprecate `sendDefaultPii`

Add the new `dataCollection` option to `ReactNativeOptions` with the relevant subset of options from the [spec]().

## Tasks

* Define `DataCollectionOptions` type with at minimum: `userInfo`, `genAIInputs`, `genAIOutputs`, `stackFrameVariables`, `frameContextLines`
* Add `dataCollection` to `ReactNativeOptions` in `options.ts`
* Deprecate `sendDefaultPii` with a JSDoc `@deprecated` annotation
* Add backward-compat bridging: if `sendDefaultPii` is set but `dataCollection` is not, map `sendDefaultPii: true` → `dataCollection: { userInfo: true }`
* Emit a console warning when `sendDefaultPii` is used, pointing to `dataCollection`
* Add tests for the bridging logic

## References

* `packages/core/src/js/options.ts` — option definitions
* Spec: [https://develop.sentry.dev/sdk/foundations/client/data-collection/]()