chore: trim observability surface docs

docs/module-data-flow.html

@@ -309,7 +309,7 @@ flowchart TB
     codec["ingest-codec-common<br/>BCD / CRC / BCC / bit 工具"]
     session["session-core<br/>设备会话、命令分发接口、会话存储"]
     identity["vehicle-identity<br/>跨协议身份解析、MySQL 绑定表"]
-    obs["observability<br/>metrics / tracing / health"]
+    obs["observability<br/>metrics / health"]
     api["ingest-api<br/>ProtocolId / RawFrame / VehicleEvent / 注解 SPI"]
     registry["HandlerRegistry<br/>按协议、命令、infoType 路由"]
     dispatcher["Dispatcher<br/>RawFrame 到 Handler 到 EventBus"]
@@ -535,7 +535,7 @@ flowchart LR
       </tr>
       <tr>
         <td>modules/core/observability</td>
-        <td>监控、指标、追踪、健康检查等横切能力。</td>
+        <td>监控、指标、健康检查等横切能力。</td>
         <td>核心管线和 Sink 运行状态。</td>
         <td>Micrometer 指标、健康信息。</td>
         <td><span class="tag green">可用性</span><span class="tag">延迟监控</span></td>