Upgrade Node.js runtime from 18 to 24 LTS #332

Context

The project currently targets Node.js 18.20, which is no longer an appropriate long-term runtime baseline.

After the package-manager migration in #331 is complete, upgrade the frontend/build runtime to Node.js 24 LTS and move pnpm from the Node 18-compatible v10 line to the current v12 line.

Dependencies

• Blocked by Migrate package manager from Yarn 3 to pnpm 10 #331.

Scope

• Update .nvmrc from Node.js 18.20 to Node.js 24 LTS.
• Update Node.js versions used by Docker/build images and CI workflows.
• Replace remaining explicit Node.js 18 references, including legacy CI configuration where still relevant.
• Upgrade pnpm 10 to pnpm 12.
• Update the packageManager metadata in package.json.
• Keep the Node.js version requirement outside package.json; do not add or require engines.node.
• Update contributor/development documentation that still references Node.js 18 or Yarn.
• Make only the compatibility changes required to run the existing frontend toolchain on Node.js 24.

Acceptance criteria

• Dependency installation succeeds on Node.js 24 using pnpm 12.
• The production frontend build succeeds on Node.js 24.
• Lint/test checks that exercise the JavaScript toolchain succeed.
• Docker image build succeeds with the updated Node.js builder/runtime tooling.
• CI no longer relies on Node.js 18.
• Documentation reflects the new Node.js and pnpm requirements.

Non-goals

• Bulk application dependency upgrades beyond changes required for Node.js 24 compatibility.
• Vue 2 → Vue 3 migration.
• Laravel Mix → Vite migration.

Broader dependency modernization should be handled separately after the runtime baseline is upgraded.

Planning

• Priority: High
• Effort: M