Add Phase Z frame slot telemetry markers

- add frame slot markers to F29 runtime partial
- collect per-cell frame slot metrics in visual runtime check
- preserve existing visual status and failure routing behavior

src/phase_z2_pipeline.py

@@ -748,7 +748,36 @@ def run_overflow_check(html_path: Path) -> dict:
                 zones.push(m);
             });
 
-            return { slide: slideM, slide_body: bodyM, zones };
+            // B5 v0 — frame_slot_metrics (per-cell measurement of [data-frame-slot-id])
+            // 현재 F29 partial 만 marker 보유 (process_column / product_column × 3 cells = 6 entries 기대).
+            // 다른 frame (F13 / F16) 은 marker 미적용 → entry 0 — 정상.
+            const frame_slot_metrics = [];
+            slide.querySelectorAll('[data-frame-slot-id]').forEach((cell) => {
+                const slotId = cell.getAttribute('data-frame-slot-id');
+                const m2 = measure(cell);
+                const parentZone = cell.closest('.zone');
+                const zonePos = parentZone
+                    ? (parentZone.getAttribute('data-zone-position') || 'unknown')
+                    : 'unknown';
+                const zoneTid = parentZone
+                    ? (parentZone.getAttribute('data-template-id') || '?')
+                    : '?';
+                frame_slot_metrics.push({
+                    zone_position: zonePos,
+                    zone_template_id: zoneTid,
+                    frame_slot_id: slotId,
+                    class_name: cell.className,
+                    clientWidth: m2.clientWidth,
+                    clientHeight: m2.clientHeight,
+                    scrollWidth: m2.scrollWidth,
+                    scrollHeight: m2.scrollHeight,
+                    excess_x: m2.excess_x,
+                    excess_y: m2.excess_y,
+                    overflowed: m2.overflowed,
+                });
+            });
+
+            return { slide: slideM, slide_body: bodyM, zones, frame_slot_metrics };
         """)
 
         screenshot_path = html_path.parent / "preview.png"