docs: record Ob.temp git history slimming

Ariver

2026-09-01 c773fcdd1f73ca6526e11bb672b8fe33e0339a77

 X1.Knomo/_knomo-system/indexes/time-buoy/time-buoy-state.json

@@ -1,11 +1,12 @@
{
   "schemaVersion": 1,
   "updatedAt": "2026-07-15T13:14:56.842Z",
   "updatedAt": "2026-08-26T08:35:52.406Z",
   "dirty": false,
   "affectedMemoIds": [],
   "expectedPeriods": [
      "2026-06",
      "2026-07",
      "2026-08"
      "2026-08",
      "2026-09"
   ]
}