feat: tidy topology layout, symbols for all device roles, drop draw.io

Topology:
- Orthogonal routing: each parent drops to its own bus lane in the gap
  below it (interval coloring prevents overlaps), color-coded per
  parent; parallel links drawn thicker. Adjacent same-row links are
  straight, other same-row links use a lane above the row.
- Port labels sit at the target device, stacked per uplink, instead of
  piling up at line midpoints.
- Crossing reduction via repeated down/up barycenter sweeps; rows wrap
  at 12 devices.
- Wide diagrams scale to page width in HTML/PDF instead of being cut off.

Symbols:
- New built-in symbols: modem/NTU (RAD), radio link, PoE injector, NAS,
  tape library, UPS/ATS and PBX.
- Detection checks the device role first, then model/manufacturer, and
  covers the common typos "Acces Point", "Controler" and "Libary".
  Rooms and cable management are hidden; UPS devices are now shown.

Removed the draw.io export format.

Bump version to 0.5.0.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

netbox_customer_export/views.py

@@ -28,20 +28,6 @@ class ScopeSelectView(LoginRequiredMixin, View):
 
 
 class ExportView(LoginRequiredMixin, View):
-    def _drawio(self, request, scope, form, opts):
-        """Nur die Topologie – als editierbare draw.io-Datei (eine Seite je Standort)."""
-        from .topology import build_graphs, render_drawio
-
-        graphs = build_graphs(scope, opts)
-        if not graphs:
-            messages.warning(request, "Keine verkabelten Geräte gefunden – es gibt keine Topologie zu exportieren.")
-            return self._render_form(request, scope, form)
-        content = render_drawio(graphs, show_ports="ports" in (opts.get("topo_details") or []))
-        response = HttpResponse(content, content_type="application/xml")
-        filename = f"topologie_{slugify(str(scope.obj)) or 'export'}_{timezone.localdate():%Y%m%d}.drawio"
-        response["Content-Disposition"] = f'attachment; filename="{filename}"'
-        return response
-
     template_name = "netbox_customer_export/export.html"
 
     def _scope(self, request, kind, pk):
@@ -68,8 +54,6 @@ class ExportView(LoginRequiredMixin, View):
             return self._render_form(request, scope, form)
 
         opts = form.cleaned_data
-        if opts["format"] == "drawio":
-            return self._drawio(request, scope, form, opts)
         blocks = []
         for key in opts["sections"]:
             blocks += SECTIONS[key].func(scope, opts)