feat: manage uploaded image retention

.env.example

@@ -2,6 +2,10 @@
 IMAGE_BIND_ADDRESS=127.0.0.1
 IMAGE_PORT=8191
 IMAGE_REPOSITORY_PATH=/home/letrhee/sam_rebuild/image
+# Persistent service state and SQLite metadata, normally on SSD storage.
+IMAGE_RUNTIME_PATH=./runtime-data
+# Optional separate bind for uploaded images, for example a ZFS dataset.
+IMAGE_UPLOAD_PATH=./runtime-data/uploads
 IMAGE_UID=1000
 IMAGE_GID=1000
 # Source CIDRs observed inside image-web. A host-native proxy normally appears
@@ -17,7 +21,16 @@ IMAGE_PUBLIC_BASES=https://sam.hided.net/image,https://sam-image.hided.net
 
 GITEA_WEBHOOK_SECRET_FILE=./secrets/gitea_webhook_secret
 IMAGE_ADMIN_SECRET_FILE=./secrets/image_admin_secret
+IMAGE_ADMIN_PANEL_PASSWORD_FILE=./secrets/image_admin_panel_password
+IMAGE_ADMIN_PANEL_SESSION_SECRET_FILE=./secrets/image_admin_panel_session_secret
 IMAGE_SYNC_CORE_SECRET_FILE=./secrets/image_sync_core_secret
 IMAGE_SYNC_CORE2026_SECRET_FILE=./secrets/image_sync_core2026_secret
 IMAGE_UPLOAD_CORE_SECRET_FILE=./secrets/image_upload_core_secret
 IMAGE_UPLOAD_CORE2026_SECRET_FILE=./secrets/image_upload_core2026_secret
+
+# Account icons are permanent. These values apply only to Tiptap content images.
+IMAGE_CONTENT_RETENTION_DAYS=730
+IMAGE_CONTENT_QUARANTINE_DAYS=30
+IMAGE_ASSET_MAINTENANCE_SECONDS=21600
+IMAGE_ASSET_TOUCH_FLUSH_SECONDS=60
+IMAGE_ADMIN_PANEL_SESSION_HOURS=8