Users' should be able to manually override root modules for a given Terraform workspace or folder. The config should be scoped resource.

"terraform.rootModules": [
  "dir1",
  "dir2/dir3",
  "otherDir"
]

The paths should be relative to the root of the folders in the workspace (not sure if we want to allow for initialization outside workspace scope, maybe as a follow-on issue to investigate).

Given the above config and the following tree structure for a single workspace folder:

.
├── dir1
│   └── main.tf 
├── someDir
│       └── main.tf 
└── dir2
    ├── notRoot
    └── dir3
        └── main.tf 

The extension should enumerate all the directories in the setting that match actual directories present and pass those to the LS. In this case it would be:

[
  "dir1",
  "dir2/dir3"
]

(You'll notice otherDir is not passed as it doesn't match anything on disk, and someDir is not passed as its not in the settings).

Optionally we may also want to support per root module expanded configuration.

"terraform.rootModules": {
  "dir1": {
    "someSetting": ""
  }, 
  "dir2/dir3": {
    "someOtherSetting": ""
  }
}