Reintroduce RTL support using BSv5 RTLCSS

[chalin]

In our move to Bootstrap v5 (BSv5), we are adopting the Bootstrap approach to RTL, as described in https://getbootstrap.com/docs/5.3/getting-started/rtl/. The good news is that we don't have to rename all properties that have logical counterparts (at least for now), since RTLCSS handles their translation appropriately.

24H2 work

• Starting over with the strategy of using a single "main" CSS file per page, using an adapted RTL CSS for RTL pages:
  RTL support via a single main style file #2093
• Review of 24H1 PRs that might need to be totally or partially reverted:
  • [BSv5] Drop import of rtl/main #1443 - nothing to revert
  • Add RTL support using BSv5 #2002 - ok except for layouts/partials/head-css.html, which is being reworked.
    Reverted via RTL support via a single main style file #2093
  • [RTL] Drop unused style files #2020 & [RTL] Add CHANGELOG entry and drop RTL for en #2021 - nothing to revert
  • [RTL] Fix top-nav position #2018 - reverted via RTL support via a single main style file #2093
  • Ensure RTL works when Docsy is used via Hugo modules #2025 - reverted via [RTL] Drop unused BS asset and scripts to fetch it #2096
• Create an rtl branch to be used during development
  Branch preview: https://rtl--docsydocs.netlify.app/
• On rtl branch, set the en language as rtl for testing purposes - [RTL] UG: set en to rtl for testing purposes #2095
• Old 24H1 issues that go away with RTL support via a single main style file #2093:
  • [RTL] Light/dark-mode dropdown menu position is pinned to the right on narrow displays #2003
  • [RTL] Footer icon-group placement and spacing issues #2005
• Test it out on the Docsy example
• Cleanup - [RTL] Drop unused BS asset and scripts to fetch it #2097
• Update the UG - [UG] Add RTL config section #2098

24H1 work - some of it reverted in H2

Entries processed (either ok as is, or reverted in whole or part), are marked with ⤴.

• ⤴ Drop import of custom Docsy RTL styling, which was designed for Bootstrap v4 - [BSv5] Drop import of rtl/main #1443
• ⤴ Add RTL support using BSv5 #2002, fixing
  [RTL] Breadcrumb separator is in the wrong place #2004
• ⤴ [RTL] Drop unused style files #2020
  [RTL] Add CHANGELOG entry and drop RTL for en #2021
• ⤴ [RTL] Fix top-nav position #2018
  • Incorrect auto margins on RTL languages #829
  • The menu does not switch sides when the site changes to RTL #2011
• ⤴ Ensure RTL works when Docsy is used via Hugo modules #2025

---

Related:

• Logo Overlaps with Menu in RTL Languages kubernetes/website#45077
• Right-to-left language support kubernetes/website#22730

Notes:

• Context: Upgrade to Bootstrap 5.2 #470
• Would a switch to Bootstrap's RTL solution help address the following as well:
  docsy theme still causes outgoing connections to Google Fonts for Arabic and Hebrew languages matrix-org/docsy#1?
  Related(?): Support non-CDN resources #605

Other:

• https://github.com/twbs/bootstrap/blob/cf9454caa00872899215603e5e036d9a824b1b11/package.json#L46

[nate-double-u]

I think we may need some upstream help to support an Arabic localization for the kubernetes.io website (using Docsy as a theme).

• Create basic structure and translate home for Arabic kubernetes/website#44902

And to link this issue to the Kubernetes site more generally, I think solving this issue will also go toward solving kubernetes/website#22730

/cc @mboukhalfa, @a-mccarthy, @sftim

[chalin]

All: as I mentioned in Slack, BS's RTL support is experimental:

Bootstrap's RTL feature is still experimental and will evolve based on user feedback. Spotted something or have an improvement to suggest? Open an issue, we'd love to get your insights.

[a-mccarthy]

+1 @nate-double-u, this would help enable new languages that have started or expressed interest in localizating Kubernetes documentation.

cc: @seokho-son

[chalin]

@a-mccarthy @seokho-son : if you (and members of your community) could upvote this issue, it would help me assess the relative importance of the feature. Thanks.

[mboukhalfa]

+1 this important since Arabic localization is in progress and expected to be alive on k8s website but the RTL issues are blocking even the preview of the progress ! this issue will greatly help

[Metal-Bat]

loved the result
gona test it more surly

it had grate positioning and no weird display of persian characters
thanks for the effort
(translation was kinda clean just fixed a verb in pull request)

one more request kinda not sure is this the place for it or not
we lost the creator of 'vazir font' to cancer and we kinda like at least try to use his font in persian pages
(and it is great honestly and it was defualt for alot of things from the beginning)
is it posable to set in this font?
https://github.com/Rava-milad/vazir-font

[chalin]

Thanks for taking a first look, and your willingness to try it out more thoroughly @Metal-Bat.

I'm going to move ahead and prepare the next official release of Docsy (#1944).

As for changing the font, see https://www.docsy.dev/docs/adding-content/lookandfeel/#fonts. I'll let others comment on how they adjust and/or include fonts, be it for multilingual projects or otherwise.

Closing this as it seems complete. I'll reopen or comment if there is more work to be done.