- Split database.py into a runtime engine (scoped `kds` DB role, used for
all request handling) and a migration engine (privileged `kitchen` role,
used only at startup to create KDS's own tables and ALTER kitchen_settings)
— KDS previously shared kitchen's full-access DB credential wholesale
- Dispose both engines on shutdown (main.py)
- Fix theme colour clash: KDS was accidentally seeded with kitchen's teal
(#0d9488) instead of its own colour — now #ea580c (orange), regenerated
PWA icons to match
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>