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>

docs/COLLECTOR-INTEGRATION.md

@@ -209,10 +209,38 @@ a column.
 | `modelnumber` | string | `Computer.modelnumberid`, scoped to the vendor when known. Model row auto-created if missing. |
 | `osname` | string | `Computer.osid`. Controlled vocab: looked up in `operatingsystems`, NOT auto-created. Unknown value -> warning (row still written, `osid` left unset). |
 | `installedsoftware` | array of `{name, version}` | `ComputerInstalledApp` rows for applications shopdb already tracks. Unknown app name -> warning, skipped. |
+| `defaultprinter` | string | The default printer's identifier (windows name / share / hostname / port IP). Resolved to a printer asset and linked PC -> printer as a `defaultprinter` relationship. Unresolved -> warning. |
+| `printers` | array of strings | All installed network printer identifiers. Each resolves to a printer asset and is linked PC -> printer as a `connectedto` relationship (the default is skipped here since it already links as `defaultprinter`). Unresolved entries -> warning. |
 
 Schema source of truth: `get_collector_schema` in `plugins/computers/plugin.py`.
 If you change the payload, change it there and re-check this table.
 
+### PC -> printer relationship sync
+
+When a payload carries `defaultprinter` and/or `printers`, the collector syncs
+`AssetRelationship` rows so a PC page shows its printers and a printer page shows
+the PCs that use it (both render in the shared Relationships card).
+
+- Resolution: each identifier is matched, first hit wins, against the printer's
+  `windowsname`, `hostname`, `sharename`, its asset number/name, then any active
+  printer communications IP. Case-insensitive except the IP (exact). An
+  identifier that resolves to nothing adds a warning and is skipped; it never
+  fails the whole push.
+- Link types: the default printer links with `defaultprinter` (directional, PC
+  is the source); every other reported printer links with `connectedto`
+  (symmetric). A printer that is both default and in `printers` links only as
+  the default.
+- Idempotent: re-reporting the same set creates no duplicate rows (an existing
+  matching row is reactivated if it was archived, otherwise left as is).
+- Stale-link archive: on every push, collector-created links to printers no
+  longer reported are set inactive. Collector-created rows are tagged in
+  `assetrelationships.label = 'collector:printers'`; only tagged rows are ever
+  archived, so links you create by hand in the UI are never touched. A payload
+  that omits BOTH printer keys leaves all existing printer links untouched
+  (report an empty `printers: []` to clear the auto links instead).
+- Response: the collector response carries `printerlinkcount` and a
+  `printerlinks` list of `{assetid, relationshiptype}` for the links kept.
+
 ### pc-type mapping (configurable per site)
 
 `pctype` (e.g. `gea-shopfloor-cmm`) maps to a shopdb Computer Type through
@@ -487,8 +515,32 @@ function Send-ShopdbCollectorReport {
         try { $pcSubType = (Get-Content -LiteralPath 'C:\Enrollment\pc-subtype.txt' -First 1 -ErrorAction Stop).Trim() } catch {}
     }
 
+    # --- Installed printers (Win32_Printer). The Default flag marks the one
+    # default printer. We report each printer's port name (an IP or a queue
+    # host for network printers) and fall back to the share/printer name, which
+    # the collector resolves flexibly against printer windowsname/hostname/IP. ---
+    $defaultPrinter = ''
+    $printerIds     = @()
+    try {
+        $printers = Get-CimInstance -ClassName Win32_Printer -ErrorAction Stop
+        foreach ($p in $printers) {
+            if ($p.Local) { continue }   # skip local-only (XPS/PDF/OneNote)
+            # Prefer the port name (IP or queue host); fall back to ShareName,
+            # then the printer Name.
+            $identity = $p.PortName
+            if (-not $identity) { $identity = $p.ShareName }
+            if (-not $identity) { $identity = $p.Name }
+            if (-not $identity) { continue }
+            $printerIds += $identity
+            if ($p.Default) { $defaultPrinter = $identity }
+        }
+        $printerIds = @($printerIds | Select-Object -Unique)
+    } catch { Write-CollectorLog "WARN printer read failed: $($_.Exception.Message)" }
+
     # --- Build payload. Field names MUST match get_collector_schema exactly. ---
     $payload = @{ hostname = $hostname }
+    if ($defaultPrinter)   { $payload['defaultprinter'] = $defaultPrinter }
+    if ($printerIds.Count) { $payload['printers']       = $printerIds }
     if ($machineNumber) { $payload['machinenumber'] = $machineNumber }
     if ($pcType)        { $payload['pctype']        = $pcType }
     if ($pcSubType)     { $payload['pcsubtype']     = $pcSubType }