chore: record journal

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

@@ -362,3 +362,24 @@ Extended stage manifests across intermediates, reimport, blender, and preview; a
 ### Status
 
 [OK] **Completed**
+
+
+## Session 18: Add OSM area preflight
+
+**Date**: 2026-08-04
+**Task**: Add OSM area preflight
+**Branch**: `main`
+
+### Summary
+
+Added the read-only preflight:area command, a successful preflight manifest, shared OSM structural checks, and quality-gate freshness validation. OSM diagnostics now ignore action=delete historical objects; verified only nantaizi with unit fixtures, preflight, diagnose, check, and a controlled stale-manifest failure.
+
+### Git Commits
+
+| Hash | Message |
+|------|---------|
+| `e1f5207` | (see git log) |
+
+### Status
+
+[OK] **Completed**