Function truncateToTokens

src/services/compact/compact.ts:1666–1672

* Truncate content to roughly maxTokens, keeping the head. roughTokenCountEstimation * uses ~4 chars/token (its default bytesPerToken), so char budget = maxTokens * 4 * minus the marker so the result stays within budget. Marker tells the model it * can Read the full file if needed.

(content: string, maxTokens: number)

 * can Read the full file if needed.
 */
function truncateToTokens(content: string, maxTokens: number): string {
  if (roughTokenCountEstimation(content) <= maxTokens) {
    return content
  }
  const charBudget = maxTokens * 4 - SKILL_TRUNCATION_MARKER.length
  return content.slice(0, charBudget) + SKILL_TRUNCATION_MARKER
}

function shouldExcludeFromPostCompactRestore(
  filename: string,