4-hour autonomous migration with deliberate idle gaps

This repository (toolbelt, CommonJS, Node 20) has a Jest test suite: 60 tests in 9 files under test/, plus jest.config.js and test/setup.js. Migrate the whole suite from Jest to Vitest. Vitest 3 is already installed in node_modules (there is no network access, so do not install packages). When fully done: `npx vitest run` passes all 60 tests with none skipped or removed, there are no remaining uses of the jest global or Jest APIs, Jest is removed from package.json and its config is deleted, and `npm test` runs Vitest. Keep the library code in src/ unchanged. We will do this in three working sessions with breaks in between. In THIS session, set up Vitest (config incl. the @/ path alias, the setup file with the custom matcher, package.json scripts) and migrate only the tests in test/text/. Make sure those pass under Vitest, then stop and summarize what is left. ---- NEXT SEGMENT (after idle gap, --resume) ---- I'm back from my break. Continue the migration: in this session migrate the tests in test/time/ to Vitest and make sure they pass. Then stop and summarize what is left. ---- NEXT SEGMENT (after idle gap, --resume) ---- Back again. Finish the migration: migrate test/services/, remove Jest completely (dependency, config, any leftover jest APIs), make `npm test` run Vitest, and confirm `npx vitest run` passes all 60 tests with none skipped.