fix(scripts): use namespace import for js-yaml

[jth-nw]

js-yaml 5.x has no default export, so `import yaml from 'js-yaml'` throws `SyntaxError: The requested module 'js-yaml' does not provide an export named 'default'`. This fails the `test-scripts` job on the Dependabot bumps (#1717, #1720), which also skips `vale-autofix`.

Changes the import to `import * as yaml from 'js-yaml'` in:

• `scripts/quality/gen-lint-digest.mjs`
• `scripts/quality/lib/dale.mjs`
• `scripts/doc-draft/slop.mjs`

The namespace import works on 4.x and 5.x. `load` and `dump` are still exported in 5.4.3, and `npm run test:scripts` passes on both 4.3.2 and 5.4.3. This PR does not bump the dependency. The Dependabot PRs can rebase onto it.

🤖 Generated with Claude Code

[github-actions]

Code Review

No issues found.

• The three changed files only call yaml.load. js-yaml exports load as a named export in 4.x (dist/js-yaml.mjs) and in 5.x, so import * as yaml works on both versions.
• No other file in the repo outside node_modules imports or requires js-yaml, so no default import is left that would break on 5.x.
• The change doesn't touch the build, the KB copy pipeline, Docusaurus config, or workflows.