Fix Webpack startup for Node 23+ by explicitly registering ts-node

[RillJ]

Recent versions of Node (v23+) attempt to interpret TypeScript files directly, which breaks when loading TS-based Webpack config files. This repo uses TypeScript config files (e.g. webpack.dev.ts, webpack.prod.ts), and previously relied on older Node behavior or indirect loading.

This PR adds -r ts-node/register to the relevant npm scripts:

• start:web
• build:default
• build:windows

This makes it compatible with newer Node versions without requiring contributors to downgrade. Existing behaviour on older versions of Node remains unchanged.

Fix for #153.

[CLAassistant]

All committers have signed the CLA.

[pimterry]

This is great, thanks @RillJ! Seems this was powered by some automatic webpack behaviour, which presumably conflicts with modern Node's approach. Doing this explicitly is much better 👍

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