fix: remove discontinued StakeCraft snapshot service

[Gunit2481]

Description

StakeCraft discontinued its Astar and Shiden archive snapshot service in August 2026, following the failure of its treasury proposals in governance (forum thread).

The snapshots page was built entirely around that service, so it currently sends node operators to a dead endpoint:

• https://all4nodes.io/, the URL in the docs, returns HTTP 200 but is now a 753-byte placeholder page with no mention of Astar, Shiden, or snapshots.
• https://snapshots.stakecraft.com/ no longer resolves in DNS.

I checked for a drop-in replacement before rewriting and there is none: RadiumBlock covers Polkadot, Kusama, Polymesh, Phala, Moonbeam and Moonriver but not Astar or Shiden, and snapshots.polkadot.io covers relay chains and system parachains only. The page is therefore generalized rather than repointed.

Changes to docs/build/nodes/snapshots.md:

• Remove the vendor-specific intro sentence and the ## Stakecraft snapshots usage heading.
• Replace the {STAKECRAFT_WEBSITE_SNAPSHOT} placeholder, which was never defined anywhere, with a generic {SNAPSHOT_URL}.
• Add a warning admonition stating no provider is currently available, and reframe the procedure around restoring a snapshot you produced yourself.
• Keep the sync-from-scratch guidance and the relay chain warp sync section, which are unaffected and still correct.

The page is kept rather than deleted, because four pages link to it (collator/secure_setup_guide/building_node.md, node-maintenance.md, archive-node/docker.md, archive-node/binary.md) and the remaining guidance is independently useful.

Also included, since it is in the same section of the same page set:

• docs/build/nodes/node-maintenance.md — the link to the snapshot page was missing its square brackets, so it rendered as bold text followed by a literal parenthesis instead of a link.

Note: the snapshot references in docs/use/how-to-guides/layer-1/governance/offchain-governance.md are governance voting-power snapshots on OpenSquare, unrelated to node database snapshots. No change needed there.

Type of Change

• Bug fix (typo, broken link, outdated information)
• New integration or tooling documentation
• New tutorial or guide
• Structural or navigation improvement
• Other

Linked Issue

None. This is a bug fix, not a new integration.

Checklist

• I have read the CONTRIBUTING.md guidelines
• The build passes locally (yarn build)
• All links in changed files are working
• Images use the <Figure> component with absolute paths (no images changed)
• Content is factual and contains no marketing language
• The file structure follows the existing documentation hierarchy

Verification

yarn build exits 0. Checked in the generated HTML rather than assumed:

• The admonition renders with its title and the alert--warning class; no literal :::warning leaks into the output. Title uses the bracket syntax established by fix: repair broken admonitions caused by Docusaurus 3.10.1 upgrade #798.
• node-maintenance now emits <a href="/docs/build/nodes/snapshots"><strong>snapshot page</strong></a>.
• The build's HTML-minifier diagnostics name only EVM/infra/explorers, nodes/collator/requirements, nodes/collator/secure_setup_guide/launch_services, nodes/collator/secure_setup_guide/secure_connection and wasm/contract_environment/explorers. Both files in this PR are absent from that list, so those warnings are pre-existing and unrelated.

[github-actions]

Visit the preview URL for this PR (updated for commit 91e6a33):

https://astar-docs--pr800-fix-remove-stakecraf-gl4vgzai.web.app

_{(expires Tue, 01 Sep 2026 13:43:46 GMT)}

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