feat(energy): connect to real DB (lingniu_prod)

Replace front-end mock data with live API backed by:
- tab_energy_hydrogen_bill (66.5K rows) joined with
  tab_hydrogen_site (internal stations) and tab_outside_hydrogen_site
  (external stations, joined via inner_site_id)
- tab_energy_electricity_bill (4.4K rows, all 龙王路充电站)

New server routes (src/server/routes/energy/):
- GET /api/energy/hydrogen/overview  → KPI + Top5 站点 + 区域占比
- GET /api/energy/hydrogen/daily?range=&customer=  → 日级 + 站点级下钻
- GET /api/energy/electric/overview  → KPI + 本月柱图 (fallback to last
  available month if current month has no data)
- GET /api/energy/electric/monthly?customer=  → 6 个月分组日级表

Business rules encoded server-side:
- 客户类型: customer_id IS NULL = 羚牛承担, NOT NULL = 外部
- 时区: DATETIME 列字面值是 UTC，分组前 +8h 转成 CST
- 数据清理: hydrogen_time >= 2024-01-01 (排除 1900 年脏数据)
- 站点名 fallback: short_name → name → fixed_station_name → station_name → '未知站点'
- 区域归一化: SUBSTRING_INDEX(city, '-', -1) 取最后一段，去掉 '省'/'市'
  让 '四川省-成都市' 和 '成都市' 合并为 '成都'

Component changes:
- All 4 components (HydrogenOverview, HydrogenDaily, ElectricOverview,
  ElectricDaily) now use useEffect + fetch with loading/error states
- HydrogenDaily filtering moved to server (range + customer params)
  → drops client-side TODAY constant + isInPick switch
- ElectricOverview chart title is dynamic: shows 'YYYY-MM 每日充电'
  when fallback kicks in (current month has no data)
- mock.ts deleted

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/modules/energy/HydrogenDaily.tsx

@@ -1,13 +1,11 @@
-import { useMemo, useState } from 'react';
+import { useEffect, useMemo, useState } from 'react';
 import { ChevronRight } from 'lucide-react';
 import { motion, AnimatePresence } from 'motion/react';
 import { BarChart, Bar, XAxis, YAxis, ResponsiveContainer, Cell, Tooltip } from 'recharts';
 import TrendBadge from './TrendBadge';
-import { HYDROGEN_DAILY } from './mock';
+import { fetchHydrogenDaily } from './api';
 import type { CustomerType, DateQuickPick, HydrogenDailyRow } from './types';
 
-const TODAY = new Date('2026-04-28');
-
 const QUICK_PICK_OPTIONS: Array<{ id: DateQuickPick; label: string }> = [
   { id: 'today',       label: '当天'     },
   { id: 'thisWeek',    label: '本周'     },
@@ -17,51 +15,25 @@ const QUICK_PICK_OPTIONS: Array<{ id: DateQuickPick; label: string }> = [
   { id: 'last30',      label: '最近30天' },
 ];
 
-function isInPick(date: string, pick: DateQuickPick): boolean {
-  const d = new Date(date);
-  switch (pick) {
-    case 'today': {
-      return d.toISOString().slice(0, 10) === TODAY.toISOString().slice(0, 10);
-    }
-    case 'thisWeek': {
-      const day = TODAY.getDay() || 7;
-      const start = new Date(TODAY); start.setDate(TODAY.getDate() - day + 1);
-      return d >= start && d <= TODAY;
-    }
-    case 'thisMonth':
-      return d.getFullYear() === TODAY.getFullYear() && d.getMonth() === TODAY.getMonth();
-    case 'thisQuarter': {
-      const q = Math.floor(TODAY.getMonth() / 3);
-      const dq = Math.floor(d.getMonth() / 3);
-      return d.getFullYear() === TODAY.getFullYear() && dq === q;
-    }
-    case 'last7': {
-      const c = new Date(TODAY); c.setDate(TODAY.getDate() - 6);
-      return d >= c && d <= TODAY;
-    }
-    case 'last30': {
-      const c = new Date(TODAY); c.setDate(TODAY.getDate() - 29);
-      return d >= c && d <= TODAY;
-    }
-  }
-}
-
 export default function HydrogenDaily() {
   const [pick, setPick] = useState<DateQuickPick>('last30');
   const [customer, setCustomer] = useState<CustomerType>('external');
   const [expanded, setExpanded] = useState<Set<string>>(new Set());
+  const [rows, setRows] = useState<HydrogenDailyRow[] | null>(null);
+  const [error, setError] = useState<string | null>(null);
 
-  const rows = useMemo<HydrogenDailyRow[]>(() => {
-    return HYDROGEN_DAILY
-      .filter(r => r.customerType === customer)
-      .filter(r => isInPick(r.date, pick))
-      .sort((a, b) => b.date.localeCompare(a.date));
+  useEffect(() => {
+    let cancelled = false;
+    setError(null);
+    fetchHydrogenDaily(pick, customer)
+      .then(r => { if (!cancelled) setRows(r); })
+      .catch(e => { if (!cancelled) setError(e instanceof Error ? e.message : String(e)); });
+    return () => { cancelled = true; };
   }, [pick, customer]);
 
   // 柱图：按日期升序，用于"从左到右时间流"
-  const trendData = useMemo(() => [...rows].sort((a, b) => a.date.localeCompare(b.date)), [rows]);
-
-  const totalKg = rows.reduce((a, r) => a + r.totalKg, 0);
+  const trendData = useMemo(() => (rows ? [...rows].sort((a, b) => a.date.localeCompare(b.date)) : []), [rows]);
+  const totalKg = (rows ?? []).reduce((a, r) => a + r.totalKg, 0);
 
   const toggle = (date: string) => setExpanded(prev => {
     const next = new Set(prev);
@@ -161,7 +133,11 @@ export default function HydrogenDaily() {
           <span />
         </div>
         {/* 主行 + 子行 */}
-        {rows.length === 0 ? (
+        {error ? (
+          <div className="px-3 py-10 text-center text-red-500 text-[12px] font-bold">加载失败：{error}</div>
+        ) : rows === null ? (
+          <div className="px-3 py-10 text-center text-slate-400 text-[12px] font-bold">加载中…</div>
+        ) : rows.length === 0 ? (
           <div className="px-3 py-10 text-center text-slate-400 text-[12px] font-bold">暂无数据</div>
         ) : rows.map(r => {
           const open = expanded.has(r.date);