I see the need to migrate from `yarn` classic (despite my sincere love
of it) because I noticed warnings in Node 24 environment about the
deprecated methods used by `yarn`, that are (most likely) not going to
be fixed, so that `yarn` classic would probably become non-operational
in Node 25/26 (in a year).

Reiterating #2067 
Based on the findings of #2427 
And using the advantage of having workspaces introduced in #2374 

- it fixes `attw` issue in workspace
- `pnpm pack` does not work in workspace
  - pnpm/pnpm#4351
  - using `working-directory` in CI
- `pnpm version` does not work in workspace, but there is a workaround
pnpm/pnpm#8064
- but it does not work due to another `npm` bug:
npm/cli#2010
  - possible solution https://www.npmjs.com/package/bumpp
- but overall clarity and consistency is much better than even `yarn@v4`
that I tried recently

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

## Summary by CodeRabbit

- **Chores**
- Migrated project tooling and workflows from Yarn to pnpm for package
management.
  - Updated all CI workflows and pre-commit hooks to use pnpm commands.
- Adjusted documentation and contributing guidelines to reflect pnpm
usage.
- Introduced a pnpm workspace configuration and updated ignore files
accordingly.
- Updated package.json scripts and resolutions to align with pnpm usage.
- Added explicit workspace dependencies in test and example projects for
improved clarity and reliability.

- **Bug Fixes**
- Improved TypeScript compatibility with a workaround for a specific
type error.

- **Refactor**
- Simplified internal scripts and utility logic by removing Ramda
dependencies and adopting native JavaScript approaches.

- **Style**
- Updated package scripts and configuration files for consistency with
pnpm standards.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

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