Upgrade Prettier to fix CI

[jabelic]

Proposal to address the current CI failure that is affecting unrelated contribution PRs such as #437.

Summary

• upgrade Prettier to 3.8.1 in both the root package and the website package
• refresh the lockfiles and reformat the repository with the new Prettier 3 output
• restore yarn ci by allowing formatting checks to parse the current config syntax correctly

Why

For example, #437 is currently failing yarn ci on prettier --check ., even though the failure is not caused by the paste-related changes in that PR itself.

Instead, the repository now includes syntax that the current Prettier 2.x setup cannot parse during CI, including:

• TypeScript satisfies in website/docusaurus.config.ts
• import attributes such as with { type: "json" } in rollup.config.mjs

Because check-format runs as part of yarn ci, unrelated contribution PRs can fail before their actual changes are evaluated. Updating the formatter first should make those PRs easier to review on their own merits.

Scope

• dependency update only for Prettier in the root package and the website package
• lockfile refresh
• formatting-only file changes produced by Prettier 3
• no intended runtime or API behavior changes

Review notes

• the branch is split into two commits to make review easier:
  • Upgrade Prettier to 3.8.1
  • Reformat repository with Prettier 3
• the large file diff is mechanical reformatting after the formatter upgrade