feat: Z-Park branding, data collection fix, buyoff pass (v1.3.0)

Branding:
- Replace all Tianpu text/colors with Z-Park (green #52c41a)
- Update login, sidebar, BigScreen, localStorage keys

Data collection:
- Populate ps_id for all 10 inverters (Phase1: 2226182, Phase2: 2226188)
- Fix docker-compose volume mount for customer config.yaml

Buyoff warning fixes:
- Installed capacity: 2200 kW / 10 Sungrow inverters (was wrong Huawei data)
- Feature flags: hide charging menu when features.charging=false
- Device total count: compute client-side from stats
- Device groups: enrich group names from metadata

Buyoff result: CONDITIONAL PASS (21/21 critical, 54/63 total)
Data accuracy: <3% deviation from iSolarCloud reference

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

docker-compose.override.yml

@@ -8,7 +8,9 @@ services:
     environment:
       - CUSTOMER=zpark
     volumes:
+      - ./core/backend:/app
       - ./customers/zpark:/app/customers/zpark:ro
+      - ./customers/zpark:/customers/zpark:ro
       - ./scripts:/app/scripts:ro
 
   frontend: