Add schema validation for collection files #369

This commit improves collection file editing and error detection
directly in the IDE. It adds YAML schema, IDE configuration and
automatic tests to validate it.

- Introduce a YAML schema for collection file.
- Use `yaml-language-server` for enhanced YAML support in VSCode.
- Add telemetry disabling in `configure_vscode.py` to respect user
  privacy.
- Add automated checks to validate YAML file structure against the
  schema.
- Remove unused properties and do not allow them in compiler.

tests/unit/application/collections/NoUnintentedInlining.spec.ts

@@ -72,6 +72,7 @@ function createTestCases(collectionsDirFromRoot: string): ITestCase[] {
     throw new Error(`Could not find any collection in ${collectionsDir}`);
   }
   const collectionFilePaths = fileNames
+    .filter((name) => !name.startsWith('.'))
     .filter((name) => name.endsWith('.yaml'))
     .map((name) => join(collectionsDir, name));
   return collectionFilePaths.map((path) => ({