Tiled Galleries: automatically transform gallery shortcode with type parameter into Tiled Gallery block

**Updated issue description based on discussion below**

### Steps to reproduce

1. Add a new post
2. In that post, add a new classic block.
3. In that classic block, add a gallery, and pick a tiled gallery type for that gallery.
4. Publish your post.
5. Come back to it in the editor, and choose the option to "convert to blocks".
6. You would expect the gallery to be transformed into a Gallery block when this one is available, but that does not seem to work; the gallery is transformed into a standard Gallery block.

**Original description below**
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**Tiled Gallery does not work when using the block editor unless Photon is enabled.**

However, this is not a requirement when using the classic editor. Working functions should be left as they are especially since they cause no adverse effect on the other changes in Jetpack .

Working functions should be left as they are especially since they cause no adverse effect on the other changes in Jetpack.

I would very much like to be able to use the tiled gallery feature when using the block editor as it does in the classic editor. Choosing a CDN should not be a forced option on the user because they want to continue using a feature that has been working without Photon, the CDN being turned on. This is particularly problematic for those of us using other CDNs. Using the Jetpack CDN is indeed quite cumbersome as deleting images or replacing them require special steps.

Continue offering tiled galleries without forcing the CDN being turned on. This will also cause a massive problem when the time comes to discontinue supporting the classic editor. Since the technology exists to make the tiled gallery to work without turning on the global Jetpack CDN it makes eminent sense to do the same for the block editor. Not doing so will result in potentially serious problems when the classic editor is discontinued if a post with a tiled gallery needs to be edited. The result will be a broken post, guaranteed, or forced use of the Jetpack CDN whether the user wants it or not.

Users who need a CDN may choose the Jetpack Photon but may also choose another one. This choice should not break their sites.

Start with the classic block editor's "convert to blocks" flow and the gallery shortcode's type parameter described in the reproduction steps. Trace how tiled gallery types are detected and converted, then verify that conversion produces a Tiled Gallery block without requiring Photon or the Jetpack CDN.

Written by the indexing model from the issue text.