chore(ledger): n22 合入后回填台账/凭证/覆盖率基线

task/n22-flush 合入（merge 6f99dea）：vol_idle_sync 空闲 flush 兜底。
Code 215,744→215,932（+188 B）、RW 1,224→1,232（+8 B）、ZI 不变；
RW_IRAM1 75,792 B（57.8%）、CCM 57,376 B（87.9%）不变——lane-f 分支侧
--no-verify 欠账清。覆盖率基线登记 vol_idle_sync.c（36/36 套件）。
凭证重盖（L0c 恢复序列）。

scripts/size_attestation.json

@@ -1,17 +1,17 @@
 {
-  "built_at": "2026-10-25T06:07:53+08:00",
-  "fingerprint": "9b2b3b209d19275aea4744529bdb7d3b14087c27765e40fb7e25ccdafe0e721d",
-  "fingerprint_files": 1396,
+  "built_at": "2026-10-25T09:28:21+08:00",
+  "fingerprint": "f326336d2f469fedf1be8db3538a2a47e83105d36abed7b1bc549cd0ab75147f",
+  "fingerprint_files": 1398,
   "fingerprint_source": "git-index",
   "gated_regions": [
     "RW_IRAM1",
     "RW_CCM"
   ],
-  "git_head": "73f9e104928472db3084e7d03acdd3e6ac68cd89",
+  "git_head": "6f99dea3a9d8638bff7e1371839cd23b31403b50",
   "map": "MDK-ARM/STM32F407-Demo/STM32F407-Demo.map",
-  "map_mtime": 1792879590,
+  "map_mtime": 1792891670,
   "pct": {
-    "ER_IROM1": 22.62,
+    "ER_IROM1": 22.63,
     "RW_CCM": 87.89,
     "RW_IRAM1": 57.82,
     "UNINIT_CCM": 18.75
@@ -19,7 +19,7 @@
   "regions": {
     "ER_IROM1": {
       "max": 1048576,
-      "size": 237140
+      "size": 237328
     },
     "RW_CCM": {
       "max": 65280,
@@ -27,7 +27,7 @@
     },
     "RW_IRAM1": {
       "max": 131072,
-      "size": 75784
+      "size": 75792
     },
     "UNINIT_CCM": {
       "max": 256,
@@ -37,9 +37,9 @@
   "schema": 2,
   "scope_note": "\u540c\u7801\u51ed\u8bc1\uff1a\u6307\u7eb9\u8986\u76d6\u56fa\u4ef6\u4f53\u79ef\u76f8\u5173\u6e90\u7801\uff0c\u53e3\u5f84\u89c1\u672c\u811a\u672c docstring",
   "sizes": {
-    "code": 215744,
+    "code": 215932,
     "ro_data": 21396,
-    "rw_data": 1224,
+    "rw_data": 1232,
     "zi_data": 131984
   },
   "threshold_pct": 92.0,