Function copyPlanForResume

src/utils/plans.ts:164–231

(
  log: LogOption,
  targetSessionId?: SessionId,
)

 *                        not the temporary session ID from before resume.
 */
export async function copyPlanForResume(
  log: LogOption,
  targetSessionId?: SessionId,
): Promise<boolean> {
  const slug = getSlugFromLog(log)
  if (!slug) {
    return false
  }

  // Set the slug for the target session ID (or current if not provided)
  const sessionId = targetSessionId ?? getSessionId()
  setPlanSlug(sessionId, slug)

  // Attempt to read the plan file directly — recovery triggers on ENOENT.
  const planPath = join(getPlansDirectory(), `${slug}.md`)
  try {
    await getFsImplementation().readFile(planPath, { encoding: 'utf-8' })
    return true
  } catch (e: unknown) {
    if (!isENOENT(e)) {
      // Don't throw — called fire-and-forget (void copyPlanForResume(...)) with no .catch()
      logError(e)
      return false
    }
    // Only attempt recovery in remote sessions (CCR) where files don't persist
    if (getEnvironmentKind() === null) {
      return false
    }

    logForDebugging(
      `Plan file missing during resume: ${planPath}. Attempting recovery.`,
    )

    // Try file snapshot first (written incrementally during session)
    const snapshotPlan = findFileSnapshotEntry(log.messages, 'plan')
    let recovered: string | null = null
    if (snapshotPlan && snapshotPlan.content.length > 0) {
      recovered = snapshotPlan.content
      logForDebugging(
        `Plan recovered from file snapshot, ${recovered.length} chars`,
        { level: 'info' },
      )
    } else {
      // Fall back to searching message history
      recovered = recoverPlanFromMessages(log)
      if (recovered) {
        logForDebugging(
          `Plan recovered from message history, ${recovered.length} chars`,
          { level: 'info' },
        )
      }
    }

    if (recovered) {
      try {
        await writeFile(planPath, recovered, { encoding: 'utf-8' })
        return true
      } catch (writeError) {