manifest: add PartMarker pctype alias so common entries reach Part Marker PCs

PartMarker was missing from the PCType alias map, so gea-shopfloor-partmarker
matched no alias set and common manifest entries gated by PCTypes (notably
Oracle Client 11.2) were pc-filtered out - Part Marker PCs never installed
Oracle. Adds @('PartMarker','gea-shopfloor-partmarker') to the alias groups.
The companion fix (adding partmarker+heattreat to Oracle's PCTypes list) lives
in the SFLD share common/manifest.json. Verified on the win11 VM: with PCType
gea-shopfloor-partmarker the Oracle entry is now evaluated (0 pc-filtered).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

playbook/shopfloor-setup/common/lib/Install-FromManifest.ps1

@@ -455,7 +455,8 @@ $script:_pcTypeAliasGroups = @(
     @('WaxAndTrace',        'gea-shopfloor-waxtrace'),
     @('Genspect',           'gea-shopfloor-genspect'),
     @('Display',            'gea-shopfloor-display'),
-    @('Heattreat',          'gea-shopfloor-heattreat')
+    @('Heattreat',          'gea-shopfloor-heattreat'),
+    @('PartMarker',         'gea-shopfloor-partmarker')
 )
 
 # Returns every alias set (each itself a string array) that contains $name.