Investigate root cause of error message truncation in TypeScript validator #321

Investigate the code path in the TypeScript validator responsible for truncating error messages.

Determine why messages such as:

Type '{ id: number; title: string; }' is missing the following properties from type 'Doc': slug, abstract, description, and 4 more.

are being truncated instead of returning the full detailed error. Identify areas in the codebase that enforce truncation, and suggest possible fixes or improvements.

This investigation should:

• Analyze where and why truncation is applied (performance, readability, etc.)
• Check if full, untruncated errors can be safely returned
• List potential side effects or downstream impacts
• Summarize findings and propose next steps