Personalization API docs not cross-linked to Client Side API docs

It is easy to end up on https://github.com/humanmade/altis-analytics/blob/master/docs/optimization-framework/personalization.md while researching personalization, but the `Altis.Analytics.on()` function may not be available because, as [the client side docs](https://docs.altis-dxp.com/analytics/native/api/client-side-api/) clarify, the analytics script which defines `on` is async and may load late. There should be a cross-link from the personalization docs to the client side API docs.

Acceptance criteria:

- [ ] [personalization.md](/docs/optimization-framework/personalization.md) links to the client-side API documentation.