Use npm to manage Prettier tool dependency

The project uses the Prettier tool to format various file types. Previously, the version of the tool used was not
controlled. This was problematic because:

- A different version of the tool may be used on the contributor's machine than on the CI runner, resulting in confusing
  failures.
- The project is immediately subject to disruption or breakage resulting from a release of the tool.

The new approach is to specify the version of the tools via the standard npm metadata files (package.json +
package-lock.json), providing the following benefits:

- Enables automated updates via Dependabot PRs
- Enables automated vulnerability alerts

.prettierignore

@@ -11,3 +11,4 @@ indexes/testdata/package_index.json
 
 # Generated files
 /.licenses/
+node_modules/

Taskfile.yml

@@ -47,6 +47,8 @@ tasks:
   # Source: https://github.com/arduino/tooling-project-assets/blob/main/workflow-templates/assets/check-prettier-formatting-task/Taskfile.yml
   general:format-prettier:
     desc: Format all supported files with Prettier
+    deps:
+      - task: npm:install-deps
     cmds:
       - npx prettier --write .
 

package.json

@@ -1,6 +1,7 @@
 {
   "devDependencies": {
     "markdown-link-check": "^3.12.1",
-    "markdownlint-cli": "^0.37.0"
+    "markdownlint-cli": "^0.37.0",
+    "prettier": "^3.3.3"
   }
 }