feat: customer frontend, Sungrow collector fixes, real data (v1.2.0)

- Add frontend/ at root (no Three.js, no Charging, green #52c41a theme)
- Fix Sungrow collector: add curPage/size params, unit conversion
- Fix station-level dedup to prevent double-counting
- Add shared token cache for API rate limit protection
- Add .githooks/pre-commit, CLAUDE.md, .gitignore
- Update docker-compose.override.yml frontend -> ./frontend
- Pin bcrypt in requirements.txt
- Add BUYOFF_RESULTS_2026-04-05.md (39/43 pass)
- Data accuracy: 0.0% diff vs iSolarCloud

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

VERSIONS.json

@@ -0,0 +1,9 @@
+{
+  "project": "zpark-ems",
+  "project_version": "1.1.0",
+  "customer": "Z-Park 中关村科技园",
+  "core_version": "1.1.0",
+  "frontend_template_version": "1.1.0",
+  "last_updated": "2026-04-05",
+  "notes": "Z-Park customer hooks + core v1.1.0"
+}