chore(task): archive OSM turn lane arrows

.trellis/workspace/dingkang/index.md

@@ -8,8 +8,8 @@
 
 <!-- @@@auto:current-status -->
 - **Active File**: `journal-1.md`
-- **Total Sessions**: 20
-- **Last Active**: 2026-08-04
+- **Total Sessions**: 21
+- **Last Active**: 2026-08-05
 <!-- @@@/auto:current-status -->
 
 ---
@@ -19,7 +19,7 @@
 <!-- @@@auto:active-documents -->
 | File | Lines | Status |
 |------|-------|--------|
-| `journal-1.md` | ~427 | Active |
+| `journal-1.md` | ~448 | Active |
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@@ -29,6 +29,7 @@
 <!-- @@@auto:session-history -->
 | # | Date | Title | Commits | Branch |
 |---|------|-------|---------|--------|
+| 21 | 2026-08-05 | Add OSM turn lane arrows | `9a23f74` | `main` |
 | 20 | 2026-08-04 | Split area preview orchestration | `396df51` | `main` |
 | 19 | 2026-08-04 | Add configurable area asset budgets | `463cb06` | `main` |
 | 18 | 2026-08-04 | Add OSM area preflight | `e1f5207` | `main` |

.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**