Windows cross-platform build support

[gbsierra]

Describe the bug
On Windows, I can not build the manifest repo.

The first err is:
"npm error code EBADPLATFORM
npm error notsup Unsupported platform for @codecov/bundle-analyzer@1.9.1: wanted {"os":"darwin,linux"} (current: {"os":"win32"})"
it can maybe be an optional dependency.

Other errs proceeding include:

• rm -rf should use shx for cross-platform compatibility
• path for CSS loading for Swagger fails
• path not found for
  "deleteOutDir": true,
  "assets": ["assets", "open-api/styles/swagger-custom.css"]

To Reproduce
Steps to reproduce the behavior:

1. Go to CONTRIBUTING.md
2. Scroll to the bottom
3. Do the 'Getting started' process with Windows/powershell

Expected behavior
I wanted to use npm install and npm run dev on Windows device.

Environment (please give information about your environment):

• Windows 11 version 24H2 (OS Build 26100.6584) and Windows 11 version 24H2 (OS Build 26100.6899)
• Using up to date manifest repo

This PR suggests these changes: PR #514