Capture response headers, body, and transactionId on every check-issue
API call; persist as boa_txn#<ts>#<action> records with 90-day TTL.
Add "Recent BoA Submissions" section to App Home showing the last 10
with click-to-copy transactionId.
Motivation: BoA support asked for a transactionId from a past
successful call and we had no way to recover it from CloudWatch
summary logs alone.
Also adds simulate-csv.cjs (dry-run preview) and stampli-uploader.sh
(launchd-invoked S3 uploader), and gitignores debug artifacts.