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>

frontend/src/pages/Login/index.tsx

@@ -52,9 +52,9 @@ export default function LoginPage() {
     }}>
       <Card style={{ width: 400, borderRadius: 12, boxShadow: '0 8px 32px rgba(0,0,0,0.3)' }}>
         <div style={{ textAlign: 'center', marginBottom: 32 }}>
-          <ThunderboltOutlined style={{ fontSize: 48, color: '#1890ff' }} />
+          <ThunderboltOutlined style={{ fontSize: 48, color: '#52c41a' }} />
           <Title level={3} style={{ marginTop: 12, marginBottom: 4 }}>
-            天普智慧能源管理平台
+            中关村医疗器械园智慧能源管理平台
           </Title>
           <Text type="secondary">零碳园区 · 智慧运维</Text>
         </div>
@@ -72,7 +72,7 @@ export default function LoginPage() {
           </Form.Item>
           <Form.Item style={{ marginBottom: 8 }}>
             <Button block loading={guestLoading} onClick={onGuestLogin}
-              style={{ borderColor: '#1890ff', color: '#1890ff' }}>
+              style={{ borderColor: '#52c41a', color: '#52c41a' }}>
               访客体验入口
             </Button>
           </Form.Item>