feat: add reports center, admin drill-down, disease filter + bug fixes + perf optimization

Frontend features:
- 报表中心 (ReportsCenter): list/detail views, diagnosis breakdown chart, CSV export
- 多级行政下钻 (AdminBreadcrumb): 湖北省→武汉市→区→街道 hierarchical drill-down
- 按病种筛选 (DiseaseFilter): multi-select diagnosis filter on monitoring + reports pages

Backend:
- Add /forecast/{days} endpoint, diagnosis filter params on cases endpoints
- Add /streets aggregation endpoint, enrich reports with real case data
- Extract shared case_loader module

Bug fixes (14):
- Fix missing /risk/forecast route (404), historyApi pointing to non-existent router
- Fix min_risk filter silently ignored in insights/hotspots
- Fix type mismatches: CaseTrendResponse, CaseStatsResponse shapes
- Fix silent .catch(() => {}) swallowing errors, fetchAlerts not clearing stale state
- Fix lru_cache caching exceptions, generateReport used cachedGet for write op
- Fix missing useEffect deps in Insights, DistrictComparison, ReportsCenter

Performance (9):
- Zustand selectors across 9 components (eliminate re-render cascades)
- Fix districtCases.sort() mutating store state, inline IIFE → memo'd component
- CaseLocationMap: React.memo, race protection, correct deps
- AlertCard: stable callbacks, TimelinePlayer: useMemo, TopNav: clock isolation
- SideNav: modules array to module scope, DiseaseFilter: memoized filter

backend/routers/reports.py

@@ -15,14 +15,16 @@ from models import (
     ReportSummary,
     ReportSection,
     ReportRecommendation,
+    DiagnosisBreakdown,
 )
 from utils.date_helpers import get_latest_date, get_available_dates
 from utils.geojson import parse_geojson_file
+from data.case_loader import get_combined_data
 
 router = APIRouter(prefix="/api/reports", tags=["reports"])
 
 
-def calculate_report_summary(grids: List[dict], period_days: int) -> ReportSummary:
+def calculate_report_summary(grids: List[dict], period_days: int, case_data=None) -> ReportSummary:
     """Calculate summary statistics for report"""
     if not grids:
         return ReportSummary(
@@ -53,7 +55,10 @@ def calculate_report_summary(grids: List[dict], period_days: int) -> ReportSumma
         elif avg_risk < avg_3d * 0.95:
             trend_direction = "improving"
 
-    total_cases = int(len(grids) * avg_risk * 0.1 * period_days)
+    if case_data is not None and len(case_data) > 0:
+        total_cases = len(case_data)
+    else:
+        total_cases = int(len(grids) * avg_risk * 0.1 * period_days)
 
     return ReportSummary(
         total_cases=total_cases,
@@ -65,6 +70,23 @@ def calculate_report_summary(grids: List[dict], period_days: int) -> ReportSumma
     )
 
 
+def compute_diagnosis_breakdown(case_data) -> list:
+    """Compute diagnosis breakdown from case data. Returns list of dicts."""
+    if case_data is None or len(case_data) == 0:
+        return []
+    breakdown = case_data.groupby(['diagnosis', 'type']).size().unstack(fill_value=0)
+    if 'outpatient' not in breakdown.columns:
+        breakdown['outpatient'] = 0
+    if 'inpatient' not in breakdown.columns:
+        breakdown['inpatient'] = 0
+    breakdown['total'] = breakdown['outpatient'] + breakdown['inpatient']
+    return [
+        {"diagnosis": str(d), "outpatient": int(row['outpatient']),
+         "inpatient": int(row['inpatient']), "total": int(row['total'])}
+        for d, row in breakdown.sort_values('total', ascending=False).head(10).iterrows()
+    ]
+
+
 def generate_report_sections(summary: ReportSummary, grids: List[Dict], period_days: int) -> List[ReportSection]:
     """Generate report sections"""
     sections = [
@@ -259,9 +281,24 @@ async def get_report(report_id: str):
 
     period_days = 1 if report_type == "daily" else 7 if report_type == "weekly" else 30
 
-    summary = calculate_report_summary(grids, period_days)
+    # Load case data for the report's date range
+    case_data = None
+    try:
+        case_data = get_combined_data()
+        if case_data is not None and len(case_data) > 0:
+            report_start = datetime.strptime(date_str, "%Y%m%d") - timedelta(days=period_days - 1)
+            report_end = datetime.strptime(date_str, "%Y%m%d")
+            case_data = case_data[
+                (case_data['date'] >= report_start) &
+                (case_data['date'] <= report_end)
+            ]
+    except Exception:
+        case_data = None
+
+    summary = calculate_report_summary(grids, period_days, case_data)
     sections = generate_report_sections(summary, grids, period_days)
     recommendations = generate_recommendations(summary, grids)
+    diagnosis_breakdown = compute_diagnosis_breakdown(case_data)
 
     metadata = ReportMetadata(
         report_id=report_id,
@@ -285,7 +322,8 @@ async def get_report(report_id: str):
         sections=sections,
         recommendations=recommendations,
         attachments=attachments,
-        timestamp=datetime.now().isoformat()
+        timestamp=datetime.now().isoformat(),
+        diagnosis_breakdown=[DiagnosisBreakdown(**d) for d in diagnosis_breakdown],
     )
 
 
@@ -336,9 +374,24 @@ async def generate_new_report(
 
     period_days = 1 if report_type == "daily" else 7 if report_type == "weekly" else 30
 
-    summary = calculate_report_summary(grids, period_days)
+    # Load case data for the report's date range
+    case_data = None
+    try:
+        case_data = get_combined_data()
+        if case_data is not None and len(case_data) > 0:
+            report_start = datetime.strptime(date, "%Y%m%d") - timedelta(days=period_days - 1)
+            report_end = datetime.strptime(date, "%Y%m%d")
+            case_data = case_data[
+                (case_data['date'] >= report_start) &
+                (case_data['date'] <= report_end)
+            ]
+    except Exception:
+        case_data = None
+
+    summary = calculate_report_summary(grids, period_days, case_data)
     sections = generate_report_sections(summary, grids, period_days)
     recommendations = generate_recommendations(summary, grids)
+    diagnosis_breakdown = compute_diagnosis_breakdown(case_data)
 
     metadata = ReportMetadata(
         report_id=report_id,
@@ -362,7 +415,8 @@ async def generate_new_report(
         sections=sections,
         recommendations=recommendations,
         attachments=attachments,
-        timestamp=datetime.now().isoformat()
+        timestamp=datetime.now().isoformat(),
+        diagnosis_breakdown=[DiagnosisBreakdown(**d) for d in diagnosis_breakdown],
     )