Function findSemanticProjectionMessageIndex

packages/runtime/src/semantic-compact.ts:1181–1187

(
  messages: readonly ModelMessage[],
  headAnchorMessageIndex: number,
)

}

function findSemanticProjectionMessageIndex(
  messages: readonly ModelMessage[],
  headAnchorMessageIndex: number,
): number | undefined {
  const candidateIndex = headAnchorMessageIndex + 1;
  return messageContainsSemanticCompactBlock(messages[candidateIndex]) ? candidateIndex : undefined;
}

function messageContainsSemanticCompactBlock(message: ModelMessage | undefined): boolean {
  if (!message) return false;