Demo reset + dev banner suppression for DEMO company

- DemoController: company-code-gated reset action (DEMO only, CSRF protected)
- SeedDataService.Remove: FK-safe topological pre-sweep, all deletes scoped to companyId
- SeedDataService: clock entries, extra seed data, updated customer/worker/job-status seeders
- CompanySettingsController + Index.cshtml: Reset Demo Data button for DEMO company users
- ReportsController + FinancialReportService: supporting report fixes
- _Layout.cshtml: suppress env banner when current company is DEMO (all auth paths)

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

src/PowderCoating.Web/Views/CompanySettings/Index.cshtml

@@ -2679,6 +2679,34 @@
     </div>
 </div>
 
+@if (ViewBag.IsDemoCompany == true)
+{
+<div class="container-fluid mt-4">
+    <div class="card border-warning">
+        <div class="card-header bg-warning bg-opacity-10 d-flex align-items-center gap-2">
+            <i class="bi bi-arrow-clockwise text-warning fs-5"></i>
+            <strong>Demo Environment</strong>
+        </div>
+        <div class="card-body">
+            <p class="mb-2">
+                This is the <strong>DEMO</strong> company. Use the button below to wipe and re-seed all
+                demo data with fresh dates. Workers and system configuration are preserved.
+            </p>
+            <p class="text-muted small mb-3">
+                Reset takes 10&ndash;30 seconds. You will be redirected here when complete.
+            </p>
+            <form asp-controller="Demo" asp-action="ResetDemoData" method="post"
+                  onsubmit="this.querySelector('button').disabled=true; this.querySelector('button').innerHTML='<span class=\'spinner-border spinner-border-sm me-2\'></span>Resetting&hellip;';">
+                @Html.AntiForgeryToken()
+                <button type="submit" class="btn btn-warning">
+                    <i class="bi bi-arrow-clockwise me-1"></i>Reset Demo Data
+                </button>
+            </form>
+        </div>
+    </div>
+</div>
+}
+
 @section Scripts {
     <script>
         $(document).ready(function () {