Better specify expected Node.js version and update to v20.19.2 (#399)

The container image was pinned to Node.js 20.18.1, see `Dockerfile`:
``` docker
FROM node:20.18.1-bullseye-slim AS base
```

But attempting to use 20.18.1 to build Storybook, you encounter an
error:
```
{
  column: 35,
  file: '/home/doshitan/projects/platform-test-nextjs/app/.storybook/main.mjs',
  length: 11,
  line: 29,
  lineText: '      nextConfigPath: path.resolve(import.meta.dirname, "../next.config.js"),',
  namespace: '',
  suggestion: ''
}
"import.meta" is not available with the "cjs" output format and will be empty
SB_CORE-SERVER_0007 (MainFileEvaluationError): Storybook couldn't evaluate your .storybook/main.mjs file.
```

This is due to a recent change[1] that switched to using
`import.meta.dirname`, a feature of Node.js ESM loading, instead of the
legacy `__dirname`. But automatic detection and loading a file as ESM is
behind a feature flag until Node.js v20.19.0[2]. Thus breaking the
Storybook build for the project's "official" Node 20.18.1 version and
container workflow.

So:
- Update Node.js version to 20.19.2
- Add specific version requirement to `package.json`, which at least
will display a warning to folks installing packages outside the
container environment.
- Use `package.json` specification to load the correct Node.js version
in CI

Which should help keep all the different environments in sync. And the
new Node.js module behavior is the default in later versions as well, so
might as well lean into it.

[1] #392
[2]
https://nodejs.org/en/blog/release/v20.19.0/#requireesm-is-now-enabled-by-default

Author: doshitan

template/.github/workflows/cd-{{app_name}}-storybook.yml.jinja

@@ -42,7 +42,7 @@ jobs:
       - name: Setup Node
         uses: actions/setup-node@v4
         with:
-          node-version: 20
+          node-version-file: ./{{ app_name }}/package.json
           cache-dependency-path: ./{{ app_name }}/package-lock.json # or yarn.lock
           cache: npm # or yarn
       - name: Setup Pages

template/.github/workflows/ci-{{app_name}}.yml.jinja

@@ -14,7 +14,7 @@ defaults:
     working-directory: ./{{ app_name }}
 
 env:
-  NODE_VERSION: 20
+  NODE_VERSION_FILE: ./{{ app_name }}/package.json
   LOCKFILE_PATH: ./{{ app_name }}/package-lock.json # or yarn.lock
   PACKAGE_MANAGER: npm # or yarn
 
@@ -31,7 +31,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v4
         with:
-          node-version: ${{'{{'}} env.NODE_VERSION {{'}}'}}
+          node-version-file: ${{'{{'}} env.NODE_VERSION_FILE {{'}}'}}
           cache-dependency-path: ${{'{{'}} env.LOCKFILE_PATH {{'}}'}}
           cache: ${{'{{'}} env.PACKAGE_MANAGER {{'}}'}}
       - run: npm ci
@@ -52,7 +52,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v4
         with:
-          node-version: ${{'{{'}} env.NODE_VERSION {{'}}'}}
+          node-version-file: ${{'{{'}} env.NODE_VERSION_FILE {{'}}'}}
           cache-dependency-path: ${{'{{'}} env.LOCKFILE_PATH {{'}}'}}
           cache: ${{'{{'}} env.PACKAGE_MANAGER {{'}}'}}
       - run: npm ci
@@ -66,7 +66,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v4
         with:
-          node-version: ${{'{{'}} env.NODE_VERSION {{'}}'}}
+          node-version-file: ${{'{{'}} env.NODE_VERSION_FILE {{'}}'}}
           cache-dependency-path: ${{'{{'}} env.LOCKFILE_PATH {{'}}'}}
           cache: ${{'{{'}} env.PACKAGE_MANAGER {{'}}'}}
       - run: npm ci
@@ -80,7 +80,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v4
         with:
-          node-version: ${{'{{'}} env.NODE_VERSION {{'}}'}}
+          node-version-file: ${{'{{'}} env.NODE_VERSION_FILE {{'}}'}}
           cache-dependency-path: ${{'{{'}} env.LOCKFILE_PATH {{'}}'}}
           cache: ${{'{{'}} env.PACKAGE_MANAGER {{'}}'}}
       - run: npm ci
@@ -95,7 +95,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v4
         with:
-          node-version: ${{'{{'}} env.NODE_VERSION {{'}}'}}
+          node-version-file: ${{'{{'}} env.NODE_VERSION_FILE {{'}}'}}
           cache-dependency-path: ${{'{{'}} env.LOCKFILE_PATH {{'}}'}}
           cache: ${{'{{'}} env.PACKAGE_MANAGER {{'}}'}}
 
@@ -123,7 +123,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v4
         with:
-          node-version: ${{'{{'}} env.NODE_VERSION {{'}}'}}
+          node-version-file: ${{'{{'}} env.NODE_VERSION_FILE {{'}}'}}
           cache-dependency-path: ${{'{{'}} env.LOCKFILE_PATH {{'}}'}}
           cache: ${{'{{'}} env.PACKAGE_MANAGER {{'}}'}}
       - run: npm ci

template/{{app_name}}/Dockerfile

@@ -1,7 +1,7 @@
 # This file is largely based on the template-application-flask Dockerfile and
 # Next.js Docker example: https://github.com/vercel/next.js/blob/canary/examples/with-docker-compose
 # =============================================================================
-FROM node:20.18.1-bullseye-slim AS base
+FROM node:20.19.2-bullseye-slim AS base
 WORKDIR /app
 
 # Install dependencies

template/{{app_name}}/package-lock.json

@@ -3,7 +3,7 @@
   "version": "0.1.0",
   "private": true,
   "engines": {
-    "node": ">=20.0.0",
+    "node": "20.19.2",
     "npm": ">=10.0.0"
   },
   "scripts": {