Parse all xcrun runtimes and associated devices for installed simulators table

Produce a markdown table with runtime os/version and nested device list. Closes Missing infos about Installed Simulators in doc... (gitlab-org/gitlab#477414 - closed)

From the MR specific pages deployment https://gitlab-org.gitlab.io/ci-cd/shared-runners/images/macos-image-inventory/mr2:

This follows the other sub-headed table pattern we already use for SDKs.

Note that you can see the duplicate rxOS (Apple Vision Pro) simulators in the list, as reported in gitlab-org/gitlab#477422 (closed). In our newer image that is rolling out for macos 14.6 we see only one Apple Vision Pro simulator.