chore(task): archive OSM turn lane arrows

.trellis/workspace/dingkang/journal-1.md

@@ -425,3 +425,24 @@ Extracted preview route, vehicle glTF, and HTML/runtime assembly from build-area
 ### Status
 
 [OK] **Completed**
+
+
+## Session 21: Add OSM turn lane arrows
+
+**Date**: 2026-08-05
+**Task**: Add OSM turn lane arrows
+**Branch**: `main`
+
+### Summary
+
+Added vendored lane-icons assets, tested OSM turn-lane arrow generation and lane-center placement, and normalized crosswalk and stop-line generation around rendered Driving lanes.
+
+### Git Commits
+
+| Hash | Message |
+|------|---------|
+| `9a23f74` | (see git log) |
+
+### Status
+
+[OK] **Completed**