feat(lsp): Add nargo capabilities for test metadata

[phated]

Description

Problem*

Resolves #2442

Summary*

This reworks types for the LSP to allow us to send back custom capabilities, such as

{
    "capabilities": {
        "codeLensProvider": {
            "resolveProvider": false
        },
        "nargo": {
            "tests": {
                "fetch": true,
                "run": true,
                "update": true
            }
        },
        "textDocumentSync": {
            "save": true
        }
    }
}

This also adds support for requesting metadata about tests, asking the LSP to run a test, and notifications for updating tests upon file save. These custom capabilities are in service of the Test Panel in vscode, but other LSP clients can decide not to implement them if they don't have testing APIs like vscode.

Documentation

• This PR requires documentation updates when merged.

  • I will submit a noir-lang/docs PR.
  • I will request for and support Dev Rel's help in documenting this PR.

It's probably worth documenting the new UI elements that will be added to the vscode extension. I'll be including screenshots in the related PR that will be linked to this.

Additional Context

PR Checklist*

• I have tested the changes locally.
• I have formatted the changes with Prettier and/or cargo fmt on default settings.

[kevaundray]

Left some nits

[TomAFrench]

This fails for me if the Nargo workspace isn't at the root of the folder open in VSCode.

The issue stems from the extension only looking in the root for a Nargo.toml file and then failing to find it.

[phated]

This fails for me if the Nargo workspace isn't at the root of the folder open in VSCode.
The issue stems from the extension only looking in the root for a Nargo.toml file and then failing to find it.

Yep, this is a limitation of our reliance on Nargo.toml and VSCode Testing API not working with file paths. I believe this is a limitation that this feature needs to accept without a much larger rework of finding the project root can happen.