Add Giscus comments system

[fflaten]

Implements Giscus as comment system for all Docs and Commands-pages. Only index-page is currently excluded.
Comments are stored and managed as discussions in specific category in the docs-repo.

Fix #251

TODO:

• Install Giscus app in docs-repo
• Enable discussion in docs-repo. Remove default categories and create a "Comments" or "Website Comments"-category of Announcement-type
• Update config
• Reswizzle after Docusaurus v3 upgrade Docusaurus v3 #272

[bravo-kernel]

Looks amazing. Perhaps comments could also be excluded for the Additional Resources section but to be honest, I think that whole section should either be dropped or totally reworked anyway. It's just a lot of very (years old) content for which a google search provides better results.

[fflaten]

Great minds. See #264 😁
Until then, comments to help crowdsource what works or not is an improvement.

[fflaten]

A few sample pages:

• Multiple threads incl. a long thread: https://deploy-preview-267--pester-docs.netlify.app/docs/commands/Add-ShouldOperator
• Locked discussion: https://deploy-preview-267--pester-docs.netlify.app/docs/contributing/introduction

What do you think @nohwnd?

[bravo-kernel]

LGTM shall we just merge this?

[fflaten]

Can't, see task list in PR details. Using my fork's discussion atm. So waiting on approval and actions from @nohwnd 🙂

[bravo-kernel]

Ahhh 🤦🏻

[fflaten]

How should we handle docs version changes? E.g. when we move /docs/* from v5 to v6 in the future, the existing comments made in v5-lifetime will show up on v6-pages which might be rewritten.

Options:

1. Is that okay? Comments can become out of date during minor upgrades and docs-upates either way.

2) Should we move to always use versioned URLs in #316 and rather redirect /docs/* to latest stable (/docs/v5/*)? That way canonical URIs used to link page -> discussion-issue always /v5, /v6 etc. Be aware, this would also show versioned URIs in Google search results

3. Is it possible to get the version inside a Docusaurus component (Giscus.js) so we can build versioned backlink-URI?

[fflaten]

Always add version here? Maybe possible to get current page version dynamically through useDocusaurusContext() to avoid hardcoding replace /docs/ with /docs/v5 for stable like we do in _redirects ?