Support trying out packed SDKs

[jonathan-conder]

Description

Support sdkcraft try. After running sdkcraft try in an SDKcraft project, the local user can use the SDK(s) it built by adding - name: try-<SDK> to a workshop definition.

Currently the SDK volume is imported synchronously (i.e. not part of the launch or refresh change). This is something we'll look to rework once we know more about the Store API (and maybe have nicer output for dynamic workshop tasks).

Another outstanding issue is cleaning up SDK volumes (and SDKs copied to the try area) when no longer in use.

Breaking changes:

• The list of installed SDKs in the workshop's metadata now tracks where the SDK came from. Existing workshops may need to be removed before switching to this branch.
• SDK volumes now include additional metadata. I don't think any of this is currently used outside of try, but it might be worth removing old volumes.

Self-review quick check

• Make decisions that cost a lot to reverse explicit in the PR description.
• Avoid nested conditions.
• Delete dead code and redundant comments.
• Normalise symmetries by sticking to doing identical things identically.

// one way to handle errors
if err := f(); err != nil {
   ...
}

// one way to handle multiple returns
val, err := f()
if err != nil {
   ...
}
...

• Check that coupled code elements, files, and directories are adjacent. For example, test data is stored as close as possible to a test.
• Put variable declaration and initialisation together.
• Divide large expressions into digestable and self-explanatory ones. Use multiple variables if required.
• Put a blank line between two logically different chunks of code.
• Follow the style guide for new error messages.

Docs

• I have checked and added or updated relevant documentation.
• I have checked and added or updated relevant release notes.
• I have included the technical author in the review.

Or:

• I confirm the PR has no implications for documentation.

[github-actions]

TICS Quality Gate

✔️ Passed

workshop

All conditions passed

See the results in the TICS Viewer

The following files have been checked for this project

• internal/daemon/api_workshops_test.go
• internal/osutil/env_test.go
• internal/osutil/env.go
• internal/osutil/export_test.go
• internal/osutil/user.go
• internal/overlord/workshopstate/request.go

Automatic-tests / code-coverage / TICS GitHub Action