chore: add package-lock.json (#120)

* chore: add package-lock.json

This enables:

* `npm audit` to find and address reported security vulnerabilities in dependencies
* `npm ci` to install faster and skip dev dependencies (suitable in CI)

... and more. Per [npm documentation]:

    This file is intended to be committed into source repositories, and serves
    various purposes:

        Describe a single representation of a dependency tree such that teammates,
	deployments, and continuous integration are guaranteed to install
        exactly the same dependencies.

	Provide a facility for users to "time-travel" to previous states of
        node_modules without having to commit the directory itself.

	Facilitate greater visibility of tree changes through readable source
        control diffs.

	Optimize the installation process by allowing npm to skip repeated
        metadata resolutions for previously-installed packages.

	As of npm v7, lockfiles include enough information to gain a complete
	picture of the package tree, reducing the need to read package.json
        files, and allowing for significant performance improvements.

[npm documentation]: https://docs.npmjs.com/cli/v9/configuring-npm/package-lock-json

* ci: use `npm ci` instead of `npm install`

Author: gthb

.github/workflows/main.yml

@@ -42,7 +42,7 @@ jobs:
             ${{ runner.OS }}-node-
             ${{ runner.OS }}-
       - name: Install dependencies
-        run: npm install
+        run: npm ci
       - run: npm test
         env:
           CI: true

.gitignore

@@ -1,6 +1,5 @@
 node_modules
 output
-package-lock.json
 .nyc_output
 coverage
 dist