Bump package manifests, logger/monitoring defaults, and README badges
to 1.4.0 covering the backup/export refactor and offline fallback.
Single-file release bundles now inject a timestamped
serviceWorkerVersion via esbuild define (previously fell back to
SW_VERSION='v1' and left PWA clients on stale caches), and the
generated DEPLOY.md lists the cache version plus the cloud-drive
OAuth secrets (ONEDRIVE_*, GOOGLE_DRIVE_*, OAUTH_REDIRECT_BASE_URL).
Centralize backup serialization in utils/backup-format.js with a
single createBackupEntry() path shared by scheduled backups, manual
backups and exports. Introduce utils/backup-index.js for KV key
listing/pruning and utils/data-hash.js for change detection,
replacing ad-hoc helpers scattered across api/secrets/backup.js,
restore.js and worker.js. UI backup/export modules consume the shared
format so HTML/JSON/CSV exports round-trip through the same schema.
