- Fix display_name → name column on Tenant model (3 files)
- Rename 'Soll vs Ist' to 'Baseline Compare' (English consistency)
- Redesign landing page: stats overview grid, critical drift banner,
severity breakdown section, proper empty states with icons
- Upgrade dashboard widget: severity badges, inline critical alert,
last compared timestamp, compliance status indicator
- Move Findings + DriftLanding from 'Drift' to 'Governance' nav group
