Issue

internal JS-6272

Description

see smithy-lang/smithy-typescript#1713

uses rollup instead of esbuild to generate the dist-cjs distribution

Testing

CI should suffice - this change affects cjs build artifacts, which are what run in Node.js, i.e. most of our automated test suite.

Checklist

• If the PR is a feature, add integration tests (*.integ.spec.ts).
• If you wrote E2E tests, are they resilient to concurrent I/O?
• If adding new public functions, did you add the @public tag and enable doc generation on the package?