Use correct pnpm `.npmrc` and `changesets` method

Implement proper `.npmrc` auth for GitHub Packages, which may be to entirely remove this file, see pnpm official docs <https://pnpm.io/npmrc>. May impact GitHub Action workflows as well.

https://github.com/facioquo/stock-charts/blob/157aace0dd37acdb7abe3292b9d6c0154527ba57/.npmrc#L1

Depends on:

- facioquo/design-system#251
- facioquo/agentics#95
- facioquo/management#88