Update old-blog ignore ranges

How to advance the year range of old blog posts excluded from site checks and fixes.

Old blog posts are historical and not updated, so they are excluded from lint/format checks and fix scripts. Once a year (or as needed), advance the year range in the configuration of each tool listed below.

Configuration to update

Each entry encodes the same policy: currently ignoring 2019 and 202[0-4]. htmltest and link extraction omit 2020 since there are no posts in that year (the glob-based tools harmlessly include it). Adjust the year ignore glob/pattern as needed for each tool:

ToolConfiguration
cspell.cspell.ymlignorePaths
markdownlint.markdownlint-cli2.yamlignores
prettier.prettierignore
textlint.textlintignore (note: requires ** glob suffixes)
fix:dict, trailing spacespackage.json__find:md:not-old-blog script
htmltest (link checker)content/en/blog/_index.mdhtmltest.IgnoreDirs
link extractionscripts/_extract-external-links.js (mirrors htmltest)

Verify

The policy is guarded by scripts/old-blog-lint-ignores.test.mjs, which seeds violations into an old and a recent blog folder and asserts that each tool skips the former and flags the latter. Run it via:

npm run test:local-tools

If the newly ignored year still has lint debt that the tools now skip, that is expected — old posts are left as is.