fix: #49 fix the bug of split chunks algorithm with rspack 2

[xfsnowind]

Summary

Fixes #49 — Disables splitChunks in the default Cypress rspack config to prevent module loading failures with Rspack v2 on Linux.

Problem

The splitChunks: { chunks: 'all' } setting (inherited from Cypress's official @cypress/webpack-dev-server) causes Rspack v2's chunk splitting algorithm to produce broken chunk boundaries on Linux. A transitive dependency gets placed in a separate chunk that hasn't loaded when the spec module evaluates, resulting in:

TypeError: Cannot read properties of undefined (reading 'call')
  at __webpack_require__

The issue is platform-specific — it reproduces on Linux (@rspack/binding-linux-x64-gnu) but not on macOS (@rspack/binding-darwin-arm64) with identical node_modules.

Why this fix is safe

Chunk splitting is not beneficial for Cypress component testing — all code runs in a single test iframe. There's no performance gain from shared vendor chunks in this context. The splitChunks config was inherited from Cypress's webpack-dev-server where it works correctly with webpack's chunk loading runtime, but Rspack v2's rewritten @rspack/dev-server (no longer based on webpack-dev-server) handles chunk loading differently.

Changes

• src/makeDefaultRspackConfig.ts: splitChunks: { chunks: 'all' } → splitChunks: false
• dist/makeDefaultRspackConfig.js: same change in compiled output