Setup wizard: plugin display names + GE-Enforce next-steps pointer

Plugins list now carries a displayname (manifest display_name, else the
machine name title-cased). Adds display_name to the four whose title-case
was wrong: GE-Enforce, USB, Measuring Tools, Knowledge Base. The setup
wizard Features step and Settings > Plugins render it, so "Geenforce"/"Usb"
are gone.

Finish step shows a pointer when GE-Enforce is enabled: it still needs a
scoped service token (Settings > API Tokens) and a share export root
(GE-Enforce page) before the fleet uses it - operational config the wizard
does not collect.

frontend build green; naming green.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

plugins/knowledgebase/manifest.json

@@ -1,5 +1,6 @@
 {
   "name": "knowledgebase",
+  "display_name": "Knowledge Base",
   "version": "1.0.0",
   "description": "Knowledge Base articles linking to external resources",
   "author": "ShopDB Team",