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.Infrastructure/Services/FinancialReportService.cs

@@ -755,17 +755,20 @@ public class FinancialReportService : IFinancialReportService
         var asOfEnd = asOf.AddDays(1).AddTicks(-1);
         var companyName = await GetCompanyNameAsync(companyId);
 
-        var openBills = await _context.Bills
+        // BalanceDue is a computed property — filter on persisted columns in SQL,
+        // then apply BalanceDue > 0 client-side after materialisation.
+        var openBills = (await _context.Bills
             .Include(b => b.Vendor)
             .Where(b => b.CompanyId == companyId
                      && b.Status != BillStatus.Draft
                      && b.Status != BillStatus.Voided
                      && b.Status != BillStatus.Paid
-                     && b.BillDate <= asOfEnd
-                     && b.BalanceDue > 0)
+                     && b.BillDate <= asOfEnd)
             .OrderBy(b => b.Vendor!.CompanyName)
             .ThenBy(b => b.DueDate)
-            .ToListAsync();
+            .ToListAsync())
+            .Where(b => b.BalanceDue > 0)
+            .ToList();
 
         static string AgingBucket(int d) => d switch
         {