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/__init__.py

@@ -5,7 +5,7 @@ class CustomerExportConfig(PluginConfig):
     name = "netbox_customer_export"
     verbose_name = "Kunden-Export"
     description = "Kundendokumentation als PDF oder Word exportieren"
-    version = "0.4.0"
+    version = "0.5.0"
     author = "Claude"
     base_url = "customer-export"
     min_version = "4.6.8"