feat: 性能优化 + 设备总览轨迹展示 + 广播指令API

性能: SQLite WAL模式、aiohttp Session复用、TCP连接锁+空闲超时、
device_id缓存、WebSocket并发广播、API Key认证缓存、围栏N+1查询
批量化、逆地理编码并行化、新增5个DB索引、日志降级DEBUG

功能: 广播指令API(broadcast)、exclude_type低精度后端过滤、
前端设备总览Tab+多设备轨迹叠加+高亮联动+搜索+专属颜色

via [HAPI](https://hapi.run)

Co-Authored-By: HAPI <noreply@hapi.run>

app/main.py

@@ -89,9 +89,14 @@ async def lifespan(app: FastAPI):
             for stmt in [
                 "CREATE INDEX IF NOT EXISTS ix_alarm_type ON alarm_records(alarm_type)",
                 "CREATE INDEX IF NOT EXISTS ix_alarm_ack ON alarm_records(acknowledged)",
+                "CREATE INDEX IF NOT EXISTS ix_alarm_source ON alarm_records(alarm_source)",
                 "CREATE INDEX IF NOT EXISTS ix_bt_beacon_mac ON bluetooth_records(beacon_mac)",
                 "CREATE INDEX IF NOT EXISTS ix_loc_type ON location_records(location_type)",
                 "CREATE INDEX IF NOT EXISTS ix_att_type ON attendance_records(attendance_type)",
+                "CREATE INDEX IF NOT EXISTS ix_att_source ON attendance_records(attendance_source)",
+                "CREATE INDEX IF NOT EXISTS ix_att_device_type_time ON attendance_records(device_id, attendance_type, recorded_at)",
+                "CREATE INDEX IF NOT EXISTS ix_device_status ON devices(status)",
+                "CREATE INDEX IF NOT EXISTS ix_fence_active ON fence_configs(is_active)",
             ]:
                 await conn.execute(sa_text(stmt))
         logger.info("Database indexes verified/created")
@@ -107,6 +112,9 @@ async def lifespan(app: FastAPI):
     logger.info("Shutting down TCP server...")
     await tcp_manager.stop()
     tcp_task.cancel()
+    # Close shared HTTP session
+    from app.geocoding import close_http_session
+    await close_http_session()
 
 app = FastAPI(
     title="KKS Badge Management System / KKS工牌管理系统",
@@ -186,12 +194,14 @@ app.include_router(geocoding.router, dependencies=[*_api_deps])
 _STATIC_DIR = Path(__file__).parent / "static"
 app.mount("/static", StaticFiles(directory=str(_STATIC_DIR)), name="static")
 
+# Cache admin.html in memory at startup (avoid disk read per request)
+_admin_html_cache: str = (_STATIC_DIR / "admin.html").read_text(encoding="utf-8")
+
 
 @app.get("/admin", response_class=HTMLResponse, tags=["Admin"])
 async def admin_page():
     """管理后台页面 / Admin Dashboard"""
-    html_path = _STATIC_DIR / "admin.html"
-    return HTMLResponse(content=html_path.read_text(encoding="utf-8"))
+    return HTMLResponse(content=_admin_html_cache)
 
 
 @app.get("/", tags=["Root"])