Section 6.1 (linter security rules) still recommends TSLint — refresh?

Section 6.1 / sections/security/lintrules.md currently recommends tslint-config-security, but TSLint was deprecated in 2019 and that package is unmaintained. The eslint-plugin-security link also points to the archived nodesecurity org instead of its current eslint-community home.

Section 3.2 has a couple of link bugs too: the text eslint-plugin-node-security links to eslint-plugin-security, eslint-plugin-node is deprecated in favor of eslint-plugin-n, there's a stray / in /eslint-plugin-jest, and eslint-plugin-require doesn't exist on npm.

I'd like to open a small English-only PR that fixes the stale links, notes the TSLint deprecation, and adds one sentence mentioning newer flat-config security plugins alongside eslint-plugin-security. Disclosure: I maintain some of those newer plugins, so I'd rather get a maintainer's nod on the framing first. Happy to keep it to pure link fixes if you prefer — the corrections stand on their own either way.