Add dismiss button to progress widget completion state

Shows an × button in the top-right of the completion card so users can
permanently hide the widget once they've seen the success message. Dismissal
is stored in localStorage (same pattern as the collapse state) so it persists
across page loads without requiring a DB migration. The widget hides itself
on the next load before any layout is shown, avoiding a flash.

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

src/PowderCoating.Web/Views/Dashboard/_ShopProgressWidget.cshtml

@@ -19,12 +19,19 @@
     <div id="shopProgressBody">
         @if (Model.AllDone)
         {
-            <div class="px-4 py-4 text-center">
-                <div class="fw-semibold mb-1" style="font-size:1rem;color:var(--pcl-ink);">Your shop is fully set up 🎉</div>
-                <div class="text-muted mb-3" style="font-size:0.85rem;">You're ready to run everything from here.</div>
-                <a href="@Url.Action("Create", "Jobs")" class="btn btn-primary btn-sm">
-                    Create job <i class="bi bi-arrow-right ms-1"></i>
-                </a>
+            <div class="px-4 py-4 d-flex align-items-center justify-content-between gap-3">
+                <div>
+                    <div class="fw-semibold mb-1" style="font-size:1rem;color:var(--pcl-ink);">Your shop is fully set up 🎉</div>
+                    <div class="text-muted mb-3" style="font-size:0.85rem;">You're ready to run everything from here.</div>
+                    <a href="@Url.Action("Create", "Jobs")" class="btn btn-primary btn-sm">
+                        Create job <i class="bi bi-arrow-right ms-1"></i>
+                    </a>
+                </div>
+                <button id="shopProgressDismiss" type="button"
+                        class="btn btn-link btn-sm text-muted p-0 flex-shrink-0 align-self-start"
+                        title="Dismiss" style="font-size:1.1rem;line-height:1;">
+                    <i class="bi bi-x-lg"></i>
+                </button>
             </div>
         }
         else