chore: fix modern npm and Windows dev workflow

[JCDuann]

Summary

This makes the local development workflow work reliably with modern npm and on Windows:

• adds the standard npm test script alias while preserving the existing npm run tests
• replaces rm -rf in build scripts with rimraf so build cleanup works cross-platform
• changes the deprecated prepublish lifecycle script to prepublishOnly and adds an explicit build script
• pins Enzyme's Cheerio dependency to a compatible prerelease via npm overrides and Yarn resolutions
• updates the test setup to define global.navigator in a way that works on modern Node versions

Why

On a clean Windows checkout with modern npm/Node:

• npm install was invoking prepublish, then failing because rm is not available on Windows.
• npm test was missing.
• the test suite failed before running because npm resolved Enzyme's nested Cheerio dependency to a newer version with package exports.
• after fixing Cheerio, modern Node exposed global.navigator as a getter, so direct assignment failed in test/setup.js.

Verification

• npm install --legacy-peer-deps --package-lock=false
• npm test -> 2102 passing
• npm run build-cjs