v1.12.2 — Cleanup safety net + calendar emoji fix

Changed

Calendar emoji 📅 → 🗓️

Apple, Discord and Slack render the old emoji with a hard-coded date number ("17") that looks like meaningful data but is purely cosmetic. The new spiral-calendar emoji has no fixed number. Replaced across notifications and all 16 language files.

Suggested by @hypnosis4u2nv in #2.

Added

Configurable cleanup grace period

The "don't delete images younger than 24h" filter is now exposed as CLEANUP_GRACE_HOURS (default 24). Increase for more safety:

Value	Meaning
24	default — same as before
168	1 week — recommended for cautious users
720	1 month — for very cautious setups

Editable via env var or Web UI. Clamped to 0–8760 (1 year).

Backup local-only images before deletion

New opt-in CLEANUP_BACKUP_LOCAL_ONLY=true — when set, locally-built images (those without a registry digest, so docker pull can't recreate them) are saved as tarballs in /data/cleanup-backups/<timestamp>/ before being removed.

Why only local images? A "backup everything" approach would lose Docker's layer-sharing in tarballs, easily turning a 5 GB cleanup gain into a 60 GB tarball mountain. Registry-pullable images don't need a local backup — docker pull already covers them. Local images, on the other hand, are unique and worth preserving.

Companion settings:

• CLEANUP_BACKUP_DAYS (default 7) — retention for backup tarballs

Cleanup result detail

The post-cleanup notification now lists which images were just removed (first 6 by name, count overflow indicator) and any backup activity. So if something important disappears, you'll see it in the channel — not just an opaque "Total reclaimed space: …" line.

Upgrade

docker pull amayer1983/docksentry:latest
docker compose up -d

No configuration changes required. Defaults preserve the old behaviour exactly.