Make .snapshots folders opt-in instead of opt-out

Describe the bug
The AL Language extension creates empty .snapshots folders in workspace folders by default.

To Reproduce
If the AL Language extension is enabled, it will create a snapshots folders in each workspace folder of a multiroot-workspace.
See the screenshots section for a more detailed repro.

Expected behavior
When you have no AL code you can disable extensions in your workspace, but why can't it be enabled and initialize if the active folder contains *.al files or a file called "app.json"?

Besides, if you're working with a multiroot-workspace and it contains AL code + additional code in other workspaceFolders (e.g. source code of a web-service or control-addin, mobile-app, etc.), you'll need to have the AL Language extension enabled.

You can specify the path for al.snapshotDebuggingPath and al.snapshotOutputPath and .gitignore the folders, etc. but why isn't this feature an opt-in, instead of opt-out?

The folders even get created in workspaceFolders (in multiroot-workspaces) which contain no .al files and no app.json or any reference to an AL project at all, i.e. it's just pollution.

Screenshots

A minimal repro, think of this as the root of a repository:

If B/Repro.al is created, this error pops up:

Along with errors while trying to populate it: "The manifest file is not valid. Unable to cast object of type 'Newtonsoft.Json.Linq.JValue' to type 'Newtonsoft.Json.Linq.JObject'.AL(AL1017)".
But if the file existed already and simply gets opened in the active editor, a more friendly warning is displayed: "The manifest is missing" with the optional codeaction "Generate Manifest", which unfortunately also creates the .snapshot folder in the root of the repo.

If Repro.code-workspace is opened, a snapshot folder is created in each of the workspace folders:

If the project is bigger and contains more folders, you can imagine how noisy these empty .snapshots folders can become and I assume this might also confuse people that are setting up new projects.

The content of the .js and .al files doesn't matter. They can just be empty so it's not hard to set up and try out.

One might argue that .snapshots should always get generated in the B folder and I won't argue with that, but I think the A folder should at least be left alone.

5. Versions:

• AL Language:
  v6.5.413786

Reproduce the issue with a multiroot workspace containing AL and non-AL folders, as described in the report, and observe when .snapshots folders are created. Trace the extension behavior responsible for workspace initialization; done should mean non-AL workspace folders are left untouched while AL projects still support snapshot functionality.