/** Shared runtime context; omit model and effort when the harness manages them dynamically. */export function buildRuntimeInstructions(runtime: {  readonly harness: string;  readonly model?: string | undefined;  readonly reasoningEffort?: string | undefined;}): string {  const harness = toSingleLine(runtime.harness);  const model = toSingleLine(runtime.model ?? "");  const effort = toSingleLine(runtime.reasoningEffort ?? "");  const modelInfo = model && model !== "auto" && model !== "default" ? `, as ${model}` : "";  const effortInfo = effort ? ` with ${effort} reasoning effort` : "";  return `<runtime_info>In case you're asked: you are running in T3 Code through the ${harness} harness${modelInfo}${effortInfo}. No need to mention this otherwise. You can embed images and videos in your response using Markdown with absolute file paths.</runtime_info>`;} function toSingleLine(value: string): string {  return value.replaceAll(/\s+/g, " ").trim();}