✨ Add @arethetypeswrong/cli (attw) as publish:attw

Validates the emitted .d.ts declarations against multiple TypeScript
module-resolution scenarios. Same rationale as publint: it validates
the publishable artifact, not the source, so it belongs in the
publish: prefix, not check:.

- Add publish:attw script using --profile esm-only (the package is
  intentionally ESM-only; CJS resolution is out of scope by design)
- Add step to CI publish job, after publish:publint and before
  npm publish
- Document the script and the esm-only rationale in project-specs.md
  and README.md
- Add 'attw' and 'arethetypeswrong' to cspell word list
- Remove unused 'stricter' word that was added speculatively before

package.json

@@ -47,10 +47,12 @@
         "test": "npm run check:tsc && node --test --strip-types \"src/**/*.test.ts\"",
         "test:ci": "c8 --reporter=text --reporter=lcov --reporter=html node --test --strip-types \"src/**/*.test.ts\"",
         "test:unit": "node --test --strip-types \"src/**/*.test.ts\"",
+        "publish:attw": "attw . --pack --profile esm-only",
         "publish:publint": "publint",
         "use:git-commit-message": "cp commit-message-template .git/COMMIT_EDITMSG || true"
     },
     "devDependencies": {
+        "@arethetypeswrong/cli": "^0.18.5",
         "@tsconfig/node26": "^26.0.1",
         "@tsconfig/strictest": "^2.0.8",
         "@types/node": "^26.4.1",