Buildings and levels for the floor map, and make every identifier searchable

The map was one picture of one floor. A second floor was added, the blueprint
changed size, and machines moved, so a position now records WHICH DRAWING its
coordinates belong to.

Buildings and levels (ADR-017). Each level owns its blueprint per theme and its
own native pixel size; assets.mapx/mapy are pixels of assets.levelid, not of the
site. A position whose level is unknown renders "level unknown" and is never
drawn on the default level, because a marker on the wrong floor plan looks
entirely correct while pointing at the wrong place.

Repositioning in bulk: filter by unplaced, needs-review or level, search, place,
confirm. Landmark recalibration solves the transform PER AXIS from landmark
pairs and never from image dimensions - the canvas grew taller without
rescaling, so a dimension-derived scale would stretch Y by 1.57 and be wrong
everywhere. It defaults to a dry run, reports what would land off the drawing,
snapshots before applying, and clears mapverifiedat because a transform is a
guess awaiting review. Snapshots restore, including the level and the review
state, and a restore snapshots first so an undo is undoable.

Search: gaugelabreference was matched only for measuring tools and
maintenancereference was matched nowhere at all, for any asset type, while
Settings happily offers both identifiers on machines and PCs. A tag an operator
is told to record has to be findable or it is a write-only field. USB devices
and printed items were unreachable from search entirely - neither is an asset,
so the generic asset search could not see them and no searcher existed; they
now match on serial, asset tag, label, bin code and gage-lab tag, honouring
isactive, with Settings toggles and result labels to match.

The retired-application rule was half a rule: GET /api/knowledgebase hid
articles whose topic application is retired while global search still returned
them and printed the retired application as the subject. A filter is only real
if every path that reaches the row applies it.

Contract to 0.20.0 (additive): Asset gained levelid and mapverifiedat, Location
gained levelid, and resolve_asset_position returns the levelid belonging to
whichever source supplied the coordinates. The five plugins that write a map
position are re-pinned. The install-list text format gained levelid as a NINTH
field, appended, because the shipped Pascal installer reads fields 0-7 by index.

That installer still compiles in one drawing's dimensions and bundles one
blueprint, so its map is accurate for the default level only; /api/maplevels is
deliberately unauthenticated so it can read both at runtime once rebuilt.
Recorded in PRINTER-INSTALLER.md section 6 along with the other known gaps.

Migration 7d33 converts an existing single-map site into one building and one
default level carrying the old map_* settings, then assigns every placed asset
and location to it. Nothing moves on screen. Old settings rows are kept so a
rollback still finds them. Verified end to end on MySQL 5.6 from a
production-shaped database.

shopdb/core/models/asset.py

@@ -117,9 +117,24 @@ class Asset(BaseModel, SoftDeleteMixin, AuditMixin):
         nullable=True
     )
 
-    # Floor map position (ADR-001: asset-specific override; nullable)
-    mapx = db.Column(db.Integer, comment='X coordinate on floor map (ADR-001)')
-    mapy = db.Column(db.Integer, comment='Y coordinate on floor map (ADR-001)')
+    # Floor map position (ADR-001: asset-specific override; nullable).
+    #
+    # Absolute pixels in the NATIVE COORDINATE SPACE OF ITS LEVEL, not of the
+    # site (ADR-017). levelid says which drawing they are pixels of, and without
+    # it a position cannot be rendered - a marker drawn on the wrong level's
+    # blueprint looks perfectly correct and points at the wrong place, so the UI
+    # shows "level unknown" rather than assuming the default.
+    mapx = db.Column(db.Integer, comment='X coordinate on this level (ADR-017)')
+    mapy = db.Column(db.Integer, comment='Y coordinate on this level (ADR-017)')
+    levelid = db.Column(
+        db.Integer, db.ForeignKey('maplevels.levelid'), nullable=True,
+        index=True,
+        comment='Which drawing mapx/mapy are pixels of (ADR-017)')
+    # When the position was last CONFIRMED against the current drawing. A bulk
+    # transform clears it, because a transform is a starting guess: the levels
+    # were redrawn and machines moved, and nothing in the coordinates says which
+    # markers are now stale. Null means "not yet reviewed on this drawing".
+    mapverifiedat = db.Column(db.DateTime, nullable=True)
 
     # Notes
     notes = db.Column(db.Text, nullable=True)
@@ -198,6 +213,10 @@ class Asset(BaseModel, SoftDeleteMixin, AuditMixin):
                     'locationname': related.location.locationname if related.location else None,
                     'mapx': related.mapx,
                     'mapy': related.mapy,
+                    # The level belongs to whichever asset supplied the
+                    # coordinates (ADR-017). Inheriting a position without its
+                    # level draws it on the borrower's drawing instead.
+                    'levelid': related.levelid,
                     'inheritedfrom': related.assetnumber
                 }
 
@@ -250,6 +269,11 @@ class Asset(BaseModel, SoftDeleteMixin, AuditMixin):
                     result['mapx'] = inherited['mapx']
                 if result.get('mapy') is None:
                     result['mapy'] = inherited['mapy']
+                # Coordinates and their level move together, always. Copying the
+                # position while leaving levelid as this asset's own is how an
+                # inherited marker lands on the wrong drawing.
+                if result.get('levelid') is None:
+                    result['levelid'] = inherited.get('levelid')
 
         # Operation/short code of the resolved location (own or inherited).
         # Derived from the location name's leading token; labels can encode a