chore: Upgrade Prettier to 3.8.3

[mrousavy]

Summary

• Upgrade Prettier to 3.8.3 across the example and library workspaces.
• Upgrade the tied ESLint Prettier integration packages to eslint-config-prettier@10.1.8 and eslint-plugin-prettier@5.5.5.
• Apply the two formatting changes surfaced by Prettier 3.8 in Nitro spec types.

Notes

• Existing Prettier options are preserved.

Validation

• bun install
• bun mmkv lint
• bun lint-ci
• bun typecheck
• bun run test
• git diff --check

Jest passed with the existing Watchman recrawl warning.

[mrousavy]

Superseded by #1063, which folds the package upgrades into one PR.