Add the dualpath-as-single-machine site toggle

Most facilities consider a Dualpath pair one physical dual-bay machine.
New site setting dualpath_single_machine (default on): the machines
list, dashboard counts, machines-by-type report, and floor map collapse
each pair to its primary bay (lower assetnumber), with combined
2007 / 2008 labels; pagination totals stay honest. Detail pages remain
per-bay and always show a dual-bay sibling banner linking the partner.
Pair resolution lives in core services and joins the plugin contract
surface (0.8.0 -> 0.9.0).

On the WJ dataset: 31 pairs collapse, machine counts 262 -> 231, map
470 assets. Toggle verified live in both states, left on.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

shopdb/core/api/assets.py

@@ -920,6 +920,18 @@ def get_assets_map():
         Asset.mapy.isnot(None)
     )
 
+    # Dualpath single-machine collapse: hide the secondary bay marker so a
+    # dual-bay pair shows one marker; the primary carries the partner label.
+    # Gated on the site setting (default on).
+    from shopdb.core.services.dualpath import (
+        resolve_dualpath_pairs, dualpath_single_machine_enabled)
+    dualpath_collapse = None
+    if dualpath_single_machine_enabled():
+        dualpath_collapse = resolve_dualpath_pairs()
+        if dualpath_collapse.secondaryassetids:
+            query = query.filter(
+                Asset.assetid.notin_(dualpath_collapse.secondaryassetids))
+
     selected_assettype = request.args.get('assettype')
 
     # Filter by asset type name
@@ -1037,6 +1049,11 @@ def get_assets_map():
         if type_data:
             item['typedata'] = type_data
 
+        # combined-label partner for a collapsed dual-bay pair (label only)
+        if dualpath_collapse:
+            partner = dualpath_collapse.partnerbyasset.get(asset.assetid)
+            item['dualpathpartner'] = partner['assetnumber'] if partner else None
+
         data.append(item)
 
     # Get filter options - these are small reference tables, no N+1 concern