Support resolving formatter settings per document

[shin19991207]

What does this PR do?

Supports resolving formatter settings per document.
This allows different folders in a multi-root workspace to use different formatter settings, including singleQuote, bracketSpacing, proseWrap, printWidth, and trailingComma.

What issues does this PR fix or reference?

Fixes redhat-developer/vscode-yaml#1240
Related to redhat-developer/vscode-yaml#1287

Is it tested? How?

• New automated test by Claude
• Manually tested with Make formatter settings resource scoped vscode-yaml#1287 in a multi-root workspace with different formatter settings for each workspace folder:
  1. Create a multi-root workspace containing two folders
  2. In the first folder's .vscode/settings.json, configure:

     {
       "yaml.format.singleQuote": true
     }

  3. In the second folder's .vscode/settings.json, configure:

     {
       "yaml.format.singleQuote": false
     }

  4. Create the same YAML document in both folders:

     root:
       - child: "text"

  5. Run Format Document in both files.

[datho7561]

Looks good and works well. Thanks, Morgan!