Finalize the renaming and migration of JS packages in the packages directory

[rtibbles]

Summary

• Migrates the hashi package to kolibri-sandbox - updates all names except those needed for backwards compatibility
• Creates a new kolibri-glob package to house our slim wrapper around glob
• Creates a kolibri-build package, specifically focused on building Javascript for plugins
• Creates a kolibri-i18n package, focused solely on extracting messages and converting to and from CSV/JSON formats
• Deletes all crowdin API code in favour of the Crowdin CLI utility
• Changes our Crowdin upload workflow to only ever have a single 'release' branch that we upload updates to, thus removing the need to transfer screenshots across releases
• Moves all non-crowdin related i18n Python code into build_tools/i18n as it is only needed in the Kolibri repository
• Instead of recreating the kolibri test behaviour, instead just creates a package that exposes the jest configuration for reuse
• Updates github action for npm publishing to include the new packages
• Adds two manually dispatched github actions - one for uploading strings to crowdin, one for downloading strings from crowdin and making a PR to commit them

References

Fixes #8454

Reviewer guidance

As long as the build passes, this will also need checking of things that use the kolibri-sandbox, such as HTML5, H5P, and Bloompub resources.
I have personally tested upload and download to crowdin, but a double check wouldn't hurt, and a review of the documentation tweaks (by doing what it says in the docs) would be helpful!

Note that I used Claude Code extensively for this, but mostly in terms of code movement, path updating, and renaming things. It also generated the two new Python utilities, for generating language mappings and cleaning up unsupported language locale folders.

[rtibbles]

Looks like I missed some cleanup here - will resolve before asking for any review.

[github-actions]

Build Artifacts

Asset type	Download link
PEX file	kolibri-0.19.0b1.dev0_git.36.g9e8de3ee.pex
Windows Installer (EXE)	kolibri-0.19.0b1.dev0+git.36.g9e8de3ee-windows-setup-unsigned.exe
Debian Package	kolibri_0.19.0b1.dev0+git.36.g9e8de3ee-0ubuntu1_all.deb
Mac Installer (DMG)	kolibri-0.19.0b1.dev0+git.36.g9e8de3ee.dmg
Android Package (APK)	kolibri-0.19.0b1.dev0+git.36.g9e8de3ee-0.1.6-debug.apk
Raspberry Pi Image	kolibri-pi-image-0.19.0b1.dev0+git.36.g9e8de3ee.zip
TAR file	kolibri-0.19.0b1.dev0+git.36.g9e8de3ee.tar.gz
WHL file	kolibri-0.19.0b1.dev0+git.36.g9e8de3ee-py2.py3-none-any.whl

[rtibbles]

I think all cleanup should have happened now.

[marcellamaki]

I've tested the different content types with the sandbox, checked the crowdin workflows by using the updated docs, and had no issues. I have not read through every line of this code, but I suspect that I wouldn't catch things in that way anyways. I think the best bet here is for this to be included in our integration testing for peter to confirm no critical regressions.