Phase 7A: wire ADR-001 asset position contract surface

Lock the position-resolution columns from ADR-001 in code so
resolve_asset_position's relationship walk activates.

Schema
- Asset.mapleft -> Asset.mapx, Asset.maptop -> Asset.mapy
- Location.mapx / Location.mapy added (fallback for priority 3 of the
  ADR-001 resolution chain)
- AssetRelationship.label (free-text nuance per ADR-001)
- AssetRelationship.inheritsposition (bool, server_default true, controls
  whether the resolved-position walk follows the edge)
- RelationshipType.propagatesthroughid (self-FK; sibling-propagation rail)

Seeds
- Three canonical ADR-001 relationship types created idempotently:
  partof, controls, connectedto
- controls.propagatesthroughid wired to partof (partof + connectedto stay
  null per ADR-001 table). Both via Alembic migration AND CLI seed command
  so a fresh test fixture and a sister-site deploy both end up correct.
- Legacy connection types (Serial Cable, Direct Ethernet, USB, WiFi,
  Dualpath) retained for backward compat with pre-1.0 relationship rows.

Resolver
- shopdb.api.resolve_asset_position now walks inheritsposition=true edges
  of type partof (then controls), recursively, depth-capped at 3 with
  visited-set cycle protection. Inactive edges + non-inheritable types
  are skipped. Falls through to the existing location fallback when the
  walk yields nothing.

Tests
- 11 new test_api_namespace cases cover: partof walk, controls-after-
  partof ordering, connectedto skipped, inheritsposition=false skipped,
  recursion, cycle break, depth-3 cap, self-beats-related, related-beats-
  location, inactive-edge skip.
- 111 tests pass. Naming/style check green.

Migration
- migrations/versions/7a01_adr001_position_contract.py:
  - alter_column renames on assets (no data loss)
  - add_column on locations + relationshiptypes + assetrelationships
  - idempotent seed of three ADR types + propagation FK wire-up
  - downgrade reverses + best-effort deletion of seeded types that have
    no FK refs

Backend rename (mapleft/maptop -> mapx/mapy)
- shopdb/core/api/assets.py
- plugins/{computers,equipment,network,printers}/api/...
- scripts/migration/migrate_assets.py
- Legacy Machine model + machines API + import_from_mysql.py UNCHANGED
  (per ADR-001 Machine retires; not part of the asset contract)

Frontend rename
- frontend/src/components/ShopFloorMap.vue
- frontend/src/views/{MapEditor.vue, pcs/{PCDetail,PCForm}.vue,
  printers/{PrinterDetail,PrinterForm}.vue,
  machines/{MachineDetail,MachineForm}.vue,
  network/NetworkDeviceForm.vue}
- Form field labels + v-model bindings + computed flags switched in
  lockstep with the backend.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

shopdb/core/api/assets.py

@@ -299,8 +299,8 @@ def create_asset():
         statusid=data.get('statusid', 1),
         locationid=data.get('locationid'),
         businessunitid=data.get('businessunitid'),
-        mapleft=data.get('mapleft'),
-        maptop=data.get('maptop'),
+        mapx=data.get('mapx'),
+        mapy=data.get('mapy'),
         notes=data.get('notes')
     )
 
@@ -339,7 +339,7 @@ def update_asset(asset_id: int):
     # Update allowed fields
     allowed_fields = [
         'assetnumber', 'name', 'serialnumber', 'assettypeid', 'statusid',
-        'locationid', 'businessunitid', 'mapleft', 'maptop', 'notes', 'isactive'
+        'locationid', 'businessunitid', 'mapx', 'mapy', 'notes', 'isactive'
     ]
 
     for key in allowed_fields:
@@ -527,7 +527,7 @@ def get_assets_map():
     """
     Get all assets with map positions for unified floor map display.
 
-    Returns assets with mapleft/maptop coordinates, joined with type-specific data.
+    Returns assets with mapx/mapy coordinates, joined with type-specific data.
 
     Query parameters:
     - assettype: Filter by asset type name (equipment, computer, network_device, printer)
@@ -617,8 +617,8 @@ def get_assets_map():
 
     query = Asset.query.options(*eager_options).filter(
         Asset.isactive == True,
-        Asset.mapleft.isnot(None),
-        Asset.maptop.isnot(None)
+        Asset.mapx.isnot(None),
+        Asset.mapy.isnot(None)
     )
 
     selected_assettype = request.args.get('assettype')
@@ -719,8 +719,8 @@ def get_assets_map():
             'name': asset.name,
             'displayname': asset.display_name,
             'serialnumber': asset.serialnumber,
-            'mapleft': asset.mapleft,
-            'maptop': asset.maptop,
+            'mapx': asset.mapx,
+            'mapy': asset.mapy,
             'assettype': asset.assettype.assettype if asset.assettype else None,
             'assettypeid': asset.assettypeid,
             'status': asset.status.status if asset.status else None,