feat(telescope): add a published picture to a page as one more dataset

[alowpoly]

telescope new-object --from-esa PAGE_ID=PICTURE_URL drafts a Hubble or Webb picture as one more dataset of a page that shows a shaped layer bank; the spec then writes the bank and bakes it. It reads the picture's page and sky tags and finds its star; a person writes the sentences and what each color takes. Run on the three dataset banks already here, it remakes them with every layer image identical. Guide.

Those banks' registration sentences change: the tags' reference pixel is counted as FITS counts it, so the tags put the star 0.10″, 0.04″ and 0.26″ away, not 0.13″, 0.21″ and 0.29″. Nothing drawn depends on it.

Also fixed: in the Local Group the two Magellanic Clouds were covered by 2,714 cluster dots of the structures field. The field no longer holds them, so each Cloud is a dot in its diamond. README.

Limits: pictures ESA publishes, on pages that already show a shaped bank. The Clouds' billboard sprites, one step closer in, are as they were.

Prepared assets

• Rebaked the three banks' indexes and the field's dots.
• Published the bytes.
• Committed the refreshed inventory.json; no baked files.

Clean: the generator's, lineage and package-consistency tests, typecheck and lint, hash, spelling, reference, growth and published-assets checks.

PR rules.