fix: avoid map refresh on road selection

.trellis/tasks/08-26-workbench-selection-save-fix/check.jsonl

@@ -0,0 +1 @@
+{"_example": "Fill with {\"file\": \"<path>\", \"reason\": \"<why>\"}. Put spec/research files only — no code paths. Run `python3 .trellis/scripts/get_context.py --mode packages` to list available specs. Delete this line once real entries are added."}

.trellis/tasks/08-26-workbench-selection-save-fix/implement.jsonl

@@ -0,0 +1 @@
+{"_example": "Fill with {\"file\": \"<path>\", \"reason\": \"<why>\"}. Put spec/research files only — no code paths. Run `python3 .trellis/scripts/get_context.py --mode packages` to list available specs. Delete this line once real entries are added."}

.trellis/tasks/08-26-workbench-selection-save-fix/prd.md

@@ -0,0 +1,16 @@
+# 修复工作台选择与保存回归
+
+## Goal
+
+道路选择只更新选择高亮，不重置地图数据或视图；保存修改后可靠保留并重新编译 overrides。
+
+## Confirmed Cause
+
+`MapCanvas` 使用 `[state, selected]` 更新全量 source 和 fit view，选择道路会触发全图重载。Road override 的前后端 schema 一致，因此保存回归需在 UI 操作后验证其状态同步和编译调用。
+
+## Acceptance Criteria
+
+- 选择道路不会清空 source、重新 fit 地图或改变视图。
+- 仅选择高亮 layer 更新；选择相关 OSM 线条样式仍刷新。
+- 暂存、保存、重新编译的 overrides 正确发送并以服务端响应更新状态。
+- 格式化、类型检查和构建通过。

.trellis/tasks/08-26-workbench-selection-save-fix/task.json

@@ -0,0 +1,26 @@
+{
+  "id": "workbench-selection-save-fix",
+  "name": "workbench-selection-save-fix",
+  "title": "修复工作台选择与保存回归",
+  "description": "修复道路选择触发全图层重建，并排查修复 React 工作台保存 overrides 回归",
+  "status": "in_progress",
+  "dev_type": null,
+  "scope": null,
+  "package": null,
+  "priority": "P2",
+  "creator": "dingkang",
+  "assignee": "dingkang",
+  "createdAt": "2026-08-26",
+  "completedAt": null,
+  "branch": null,
+  "base_branch": "main",
+  "worktree_path": null,
+  "commit": null,
+  "pr_url": null,
+  "subtasks": [],
+  "children": [],
+  "parent": null,
+  "relatedFiles": [],
+  "notes": "",
+  "meta": {}
+}

workbench/client/src/components/MapCanvas.tsx

@@ -4,7 +4,7 @@ import View from 'ol/View';
 import Select from 'ol/interaction/Select';
 import { click } from 'ol/events/condition';
 import type { Road, WorkbenchState } from '../types/state';
-import { createLayers, updateLayers, type LayerName } from '../map/layers';
+import { createLayers, updateLayers, updateSelectedRoad, type LayerName } from '../map/layers';
 
 interface Props {
   state: WorkbenchState;
@@ -72,7 +72,13 @@ export function MapCanvas({ state, selected, visible, scene, onSelectRoad, onFea
     updateLayers(layers, state, selected);
     const extent = layers.osm.getSource()!.getExtent();
     if (extent && Number.isFinite(extent[0])) map.getView().fit(extent, { padding: [48, 48, 48, 48], maxZoom: 19 });
-  }, [state, selected]);
+  }, [state]);
+  useEffect(() => {
+    const layers = layersRef.current;
+    if (!layers) return;
+    updateSelectedRoad(layers, selected);
+    layers.osm.changed();
+  }, [selected]);
   useEffect(() => {
     const layers = layersRef.current;
     if (!layers) return;

workbench/client/src/map/layers.ts

@@ -157,9 +157,14 @@ export function updateLayers(layers: ReturnType<typeof createLayers>, state: Wor
       .filter((item) => item.geometry)
       .map(({ geometry, ...properties }) => ({ type: 'Feature', properties, geometry: geometry! })),
   });
-  put('selectedRoad', { type: 'FeatureCollection', features: [] });
+  updateSelectedRoad(layers, selected);
+}
+
+export function updateSelectedRoad(layers: ReturnType<typeof createLayers>, selected: Road | null) {
+  const source = layers.selectedRoad.getSource()!;
+  source.clear();
   if (selected)
-    get('selectedRoad').addFeature(
+    source.addFeature(
       new Feature({ geometry: new LineString(selected.centerline).transform('EPSG:4326', 'EPSG:3857') }),
     );
 }