Note stable region row families across saves

crates/rrt-runtime/src/smp.rs

@@ -5344,6 +5344,10 @@ fn build_periodic_company_service_trace_report(
     notes.push(
         "Direct local binary inspection now also gives the tri-lane a concrete live runtime role: 0x0040c9a0 folds [site+0x310/+0x338/+0x360] into the local scalar band [site+0x2b4/+0x2b8/+0x2bc], mirrors the nine-dword side array rooted at [site+0x2e4], and then clears the tri-lane. Caller census keeps that accumulator role narrow too: 0x0040c9a0 only appears under the broad live-collection sweep 0x0040a3a1..0x0040a4d3, while 0x0040cac0 stays under weighted scoring/evaluation families such as 0x0040fcc0..0x0040fe28 and 0x00422c62..0x00422d3c. The direct writer strip is grounded too: 0x0040d450 writes [site+0x310] through owner-company-aware scoring, and the broader 0x00410b30..0x004118f4 candidate-processing loop writes [site+0x310/+0x338/+0x360] after gating rows through 0x00412560.".to_string(),
     );
+    notes.push(
+        "Cross-save compare now tightens the save-native side too: `compare_save_region_fixed_row_run_candidates` keys the pre-region-header fixed-row bands by lane-shape fingerprint because grounded saves do not keep one stable top rows_offset, but they do retain shared shape-family matches. The tri-lane-adjacent save seam should therefore be treated as a stable row-family problem, not a fixed-offset problem."
+            .to_string(),
+    );
     notes.push(
         "Direct local binary inspection now grounds the cached-candidate restore bridge too: the placed-structure stream-load owner 0x00413280 dispatches per-entry vtable slot +0x40 on the 0x005c8c50 specialization table, that slot resolves to 0x0040ce60, and 0x0040ce60 immediately re-enters 0x0040cd70 plus 0x0045c150. So the acquisition-side cached source/candidate bridge [site+0x3cc/+0x3d0] is no longer a generic restore mystery for stream-loaded rows; the remaining restored-row gaps are [site+0x276] and the deferred tri-lane.".to_string(),
     );

docs/rehost-queue.md

@@ -91,6 +91,10 @@ Working rule:
   - the save-side fixed-row run candidate family is now also the next save-slice seam to keep
     first-class once grounded, because it is the closest save-native candidate family to the
     still-missing cached tri-lane inputs behind `[site+0x310/+0x338/+0x360]`
+  - cross-save fixed-row comparison is tighter now too:
+    `runtime compare-region-fixed-row-runs p.gms q.gms` shows shared shape-family matches even
+    though the best raw `rows_offset` drifts between saves, so the tri-lane-adjacent row family
+    should be treated as a stable shape-family seam rather than a fixed-offset seam
 - Direct disassembly now narrows that acquisition strip further:
   - `0x004014b0` scans the live placed-structure collection at `0x0062b26c`
   - `0x0041f6e0 -> 0x0042b2d0` is the center-cell token gate over the current region