feat: Add warning for ignored type errors

[vinnymac]

Summary

Users will now know that type errors exist, but that NextJS chooses to ignore them. This helps developers understand the differences between running next build and tsc, and why they may produce different results.

I found the current behavior to be surprising, and would expect at least a warning when type errors are ignored. Perhaps this is also worth mentioning in the documentation somewhere (unless I missed it)?

Bug

• [ ] Related issues linked using fixes #number
• [ ] Integration tests added
• [ ] Errors have a helpful link attached, see contributing.md

Feature

• [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
• [ ] Related issues linked using fixes #number
• [ ] Integration tests added
• [ ] Documentation added
• [ ] Telemetry added. In case of a feature if it's used or not.
• [ ] Errors have a helpful link attached, see contributing.md

Documentation / Examples

• [ ] Make sure the linting passes by running pnpm lint
• [ ] The "examples guidelines" are followed from our contributing doc