chore: record journal

.trellis/workspace/dingkang/index.md

@@ -8,8 +8,8 @@
 
 <!-- @@@auto:current-status -->
 - **Active File**: `journal-1.md`
-- **Total Sessions**: 24
+- **Total Sessions**: 25
-- **Last Active**: 2026-08-05
+- **Last Active**: 2026-08-06
 <!-- @@@/auto:current-status -->
 
 ---
@@ -19,7 +19,7 @@
 <!-- @@@auto:active-documents -->
 | File | Lines | Status |
 |------|-------|--------|
-| `journal-1.md` | ~512 | Active |
+| `journal-1.md` | ~533 | Active |
 <!-- @@@/auto:active-documents -->
 
 ---
@@ -29,6 +29,7 @@
 <!-- @@@auto:session-history -->
 | # | Date | Title | Commits | Branch |
 |---|------|-------|---------|--------|
+| 25 | 2026-08-06 | Cesium traffic signal countdowns | `0e1574f` | `main` |
 | 24 | 2026-08-05 | 拆分 LowPoly Cars 车辆资产 | `3108336`, `2489b8a` | `main` |
 | 23 | 2026-08-05 | 车辆连续巡航与转弯 | `30846b6` | `main` |
 | 22 | 2026-08-05 | Cesium semantic inspection preview | `607d8fc` | `main` |

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

@@ -510,3 +510,24 @@ Added semantic Cesium inspection assets and controls; fixed compressed metadata
 ### Status
 
 [OK] **Completed**
+
+
+## Session 25: Cesium traffic signal countdowns
+
+**Date**: 2026-08-06
+**Task**: Cesium traffic signal countdowns
+**Branch**: `main`
+
+### Summary
+
+Added shared 7LED countdown geometry, split dynamic Cesium assets by phase group for reliable lamp-matched colors, documented the inverse-font and exporter grouping contracts, and verified the preview asset and Blender Python test suites.
+
+### Git Commits
+
+| Hash | Message |
+|------|---------|
+| `0e1574f` | (see git log) |
+
+### Status
+
+[OK] **Completed**