Compress database backups with gzip (.sql.gz), reducing file size ~83%.
Add backup retention configuration to Instance Settings UI with preset
options (7 days, 2 weeks, 1 month). The backup scheduler now reads
retention from the database on each tick so changes take effect without
restart. Default retention changed from 30 to 7 days.
Introduce a singleton instance_settings store and experimental settings API, add the Experimental instance settings page, and gate execution workspace behavior behind the new enableIsolatedWorkspaces flag.
Co-Authored-By: Paperclip <noreply@paperclip.ing>
