Fix thumbnails for prominent link to Graphers / Explorers

[ikesau]

An idea at a fix for #2870

I really can't see how prominent links were working with plain Grapher URLs before, except I know they were. Something must have been removed at some point. 😓

Anyway, this adds a little fork at the Prominent Link level, to load via the Grapher preview worker instead of via the Image attachments system. It doesn't currently take the query string into account, that but seems like an improvement over it breaking.

Example Archie

{.prominent-link}
url: https://ourworldindata.org/grapher/life-expectancy
{}

{.prominent-link}
url: https://ourworldindata.org/explorers/poverty-explorer
{}

Results

@marcelgerber do you think this is an okay way to do this? In my mind this is the same sort of dependency as DATA_API_URL , but maybe there are reasons we don't want to add this?

If we go with this we also might want to look at how BAKED_GRAPHER_EXPORTS_BASE_URL is formed

[marcelgerber]

Hm, this is interesting.

Afaict, the only problem that we had before is that <Image filename={BAKED_GRAPHER_EXPORTS_BASE_URL + "/SLUG.svg"} /> didn't work, because Image.ts couldn't find any metadata for that image (makes sense!).
On the other hand, going with <img src={BAKED_GRAPHER_EXPORTS_BASE_URL + "/SLUG.svg"} /> instead works just fine!

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As I think we've discussed before, I'm still a bit hesitant to go with the thumbnails worker in more places because while it's working great in most cases, there are some charts (e.g. covid charts) where it fails, and it sometimes takes a few seconds to render a thumbnail...