chore: move next version into versioned_docs folder

[qweeah]

What is done

All docs about next version of ORAS, as well as the community docs are moved from ./docs to ./versioned_docs/version-next

Folder structure before the change:

> tree
.
├── docs                       <--- docs of next version
├── versioned_docs
│   ├── version-1.1            <--- docs of version v1.1.0
│   └── version-1.2            <--- docs of version v1.2.0
...

Folder structure after the change:

> tree
.
├── versioned_docs
│   ├── static
│   ├── version-1.1            <--- docs of version v1.1.0
│   ├── version-1.2            <--- docs of version v1.2.0
│   └── version-next           <--- docs of next version
...

Why it's needed

After merging of #316, when I start to work on #324, I am totally lost on which file should I modify so that only documents regarding v1.2.0 can be changed. To align the folder structure and avoid such confusion, it's better to place all the documents into versioned-docs with dedicated folder for each version.

[qweeah]

Seems that how documentations in docs are not referencing static folder in a unified way, that's why I need to copy static folder to both versioned_docs and version-next at the same time.

[FeynmanZhou]

@qweeah After moving the static folder, the icons svg seems not available on the preview link: https://deploy-preview-338--oras-project.netlify.app/docs/1.2/

[TerryHowe]

Since we don't build an artifact for each commit on main, I was wondering if we should have a next at all. The more copies, the more changes we are going to lose between releases.

Can we just create the next release off the latest when we get a release candidate?

[qweeah]

@qweeah After moving the static folder, the icons svg seems not available on the preview link: https://deploy-preview-338--oras-project.netlify.app/docs/1.2/

@FeynmanZhou It's true, the icons are missing but I checked other PR's preview deployment (e.g. https://deploy-preview-340--oras-project.netlify.app/) and all those icons are missing. I think it's a bug in the netlify preview environment.

[qweeah]

Can we just create the next release off the latest when we get a release candidate?

The jumbled reference comes from community folder, which should not belong to any release but it's currently put into the next release docs.

[qweeah]

closing as #344 is a better option.