Add server-side dismiss persistence and SuperAdmin onboarding progress page

Progress widget dismiss now POSTs to Dashboard/DismissProgressWidget, writing
GuidedActivationDismissedAt to the DB so the widget stays hidden across devices
and cache clears (localStorage alone wasn't enough). BuildShopProgressWidgetAsync
suppresses the widget server-side when AllDone + dismissed.

New SuperAdmin page at /OnboardingProgress shows the activation funnel across
all tenant companies: wizard status, chosen path, milestone progress bar, key
dates (first job/quote, first invoice, workflow completed, widget dismissed),
and a status badge (Not Started / In Progress / Complete / Dismissed). Nav link
added under Users & Activity in the Platform Management sidebar.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/PowderCoating.Web/wwwroot/js/shop-progress-widget.js

@@ -38,6 +38,14 @@
         dismiss.addEventListener('click', function () {
             widget.style.display = 'none';
             try { localStorage.setItem(DISMISSED_KEY, '1'); } catch (e) { }
+            // Persist server-side so dismissal survives cache clears and other devices
+            var token = document.querySelector('input[name="__RequestVerificationToken"]');
+            if (token) {
+                fetch('/Dashboard/DismissProgressWidget', {
+                    method: 'POST',
+                    headers: { 'RequestVerificationToken': token.value }
+                }).catch(function () {});
+            }
         });
     }
 }());