Add collector PC->printer links and searchable custom fields

Collector: the computers collector schema gains defaultprinter and
printers; apply_collector_payload resolves each reported identifier to
a printer asset (windowsname/hostname/sharename/assetnumber/IP,
first-hit case-insensitive) and idempotently syncs relationships -
defaultprinter (directional) for the default, connectedto for the
rest. Collector-created rows are tagged so a re-report archives dropped
links while manual relationships are never touched; unresolved
identifiers warn instead of failing. Both PC and printer detail pages
show the links via the shared relationships card (no frontend change).
GE-Enforce Win32_Printer collection snippet documented.

Searchable custom fields: a per-field searchable flag (migration 7d24);
global search matches custom-field values on flagged active fields and
routes each hit to the asset detail page, reusing the existing
(type,id) dedupe and search_<type>_enabled domain filter. Searchable
toggle on the Custom Fields settings page.

822 tests pass; both verified live.

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

shopdb/core/api/search.py

@@ -12,7 +12,8 @@ from sqlalchemy.orm import joinedload
 from shopdb.extensions import db
 from shopdb.core.models import (
     Application, Setting,
-    Asset, AssetType, Communication, Vendor, Model
+    Asset, AssetType, Communication, Vendor, Model,
+    CustomField, CustomFieldValue
 )
 from shopdb.core.api.settings import get_cached_settings
 from shopdb.utils.responses import success_response
@@ -343,6 +344,41 @@ def _search_measuringtools(query, search_term):
     return results
 
 
+def _search_customfields(query, search_term):
+    """Search custom-field VALUES for fields flagged searchable.
+
+    Joins CustomFieldValue -> CustomField (searchable + active) -> Asset (active)
+    and emits a normal asset result routed to that asset's detail page. Results
+    are deduped against built-in-field asset matches by the shared (type, id) key
+    in global_search, and the asset's search_<type>_enabled domain toggle is
+    applied by the same end-of-request domain filter. The matched field label is
+    put in the subtitle so a value hit reads sensibly.
+    """
+    results = []
+    try:
+        rows = db.session.query(Asset, CustomField).join(
+            CustomFieldValue, CustomFieldValue.assetid == Asset.assetid
+        ).join(
+            CustomField, CustomField.fieldid == CustomFieldValue.fieldid
+        ).options(
+            joinedload(Asset.assettype),
+            joinedload(Asset.location),
+        ).filter(
+            Asset.isactive == True,
+            CustomField.searchable == True,
+            CustomField.isactive == True,
+            CustomFieldValue.value.ilike(search_term),
+        ).limit(15).all()
+
+        for asset, field in rows:
+            result = _get_asset_result(asset, query, relevance=40)
+            result['subtitle'] = field.label
+            results.append(result)
+    except Exception as e:
+        logger.error(f"Custom field search failed: {e}")
+    return results
+
+
 def _search_by_ip(query, search_term):
     """Search Communications table for IP address matches."""
     results = []
@@ -799,6 +835,7 @@ def global_search():
     results.extend(_search_employees(query, search_term))
     results.extend(_search_assets(query, search_term))
     results.extend(_search_measuringtools(query, search_term))
+    results.extend(_search_customfields(query, search_term))
     results.extend(_search_notifications(query, search_term))
     results.extend(_search_hostnames(query, search_term))
     results.extend(_search_vendor_model_type(query, search_term))