feat(go-crm): industrial terminal-core UI redesign

Complete visual overhaul of the go-crm web interface:

- New shared layout system (internal/templates/ui.go) with dark zinc
  industrial theme, JetBrains Mono typography, grid/noise textures
- Redesigned all pages: Dashboard, Login/Signup, Clients, Customers,
  Services, Scheduling, Payments, Questions, Answers, Leads,
  Review Queue, Report, Keyword Mapping
- Tailwind CSS via CDN with custom color palette (amber/emerald/rose/sky)
- HTMX-powered interactions with CSS swap animations
- Status pills, KPI cards, data tables, empty states, inline forms
- Mobile-responsive sidebar with collapsible navigation
- All existing tests updated and passing
- Zero new build dependencies — works with existing go run/air workflow

apps/go-crm/internal/handlers/status_test.go

@@ -111,7 +111,7 @@ func TestListClientsWhatsAppStatusIndicators(t *testing.T) {
 		t.Error("expected Connect link for clients without active connection")
 	}
 
-	greenDot := `color:#28a745`
+	greenDot := `bg-emerald-400`
 	if !strings.Contains(body, greenDot) {
 		t.Error("expected green dot for connected client")
 	}