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/config.py

@@ -50,6 +50,9 @@ class Settings(BaseSettings):
     # Track query limit
     TRACK_MAX_POINTS: int = Field(default=10000, description="Maximum points returned by track endpoint")
 
+    # TCP connection
+    TCP_IDLE_TIMEOUT: int = Field(default=600, description="Idle timeout in seconds for TCP connections (0=disabled)")
+
     # Fence auto-attendance
     FENCE_CHECK_ENABLED: bool = Field(default=True, description="Enable automatic fence attendance check on location report")
     FENCE_LBS_TOLERANCE_METERS: int = Field(default=200, description="Extra tolerance (meters) for LBS locations in fence check")