build(deps): bump TypeScript to 6.0.3

[ledsun]

Summary

• bump only TypeScript from 5.9.2 to 6.0.3
• make the existing compiler behavior explicit for TypeScript 6
• separate and resolve the TypeScript blocker before build(deps): bump the dependencies group across 1 directory with 11 updates #614 can proceed

Compatibility changes

• set rootDir explicitly as required by TypeScript 6
• preserve the previous non-strict behavior and Node type inclusion
• suppress the moduleResolution=node10 deprecation while retaining the current module resolution semantics
• skip conflicts between TypeScript 6 built-in declarations and external Node declarations
• use a TypeScript 5-compatible deprecation setting for Rollup, whose plugin resolves the repository-root TypeScript version

Verification

bundle exec rake npm:ruby-wasm-wasi:build

The Rollup UMD outputs and the subsequent ESM/CJS TypeScript builds complete successfully.