The 'template not found' fallback used Write-Warning, which emits 'WARNING: Plan template not found' on the warning stream -- diverging from the bash twin (echo 'Warning: Plan template not found' to stderr in --json, stdout in text mode) in both wording and routing, and inconsistent with the sibling 'Copied plan template' message (#3198) in the same block. Route it the same way so the two scripts share one status-output contract.
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>