Render preview uses the shared camera navigation (#1462)

* Render preview uses the shared camera navigation

The Render workspace's product preview had its own hard-coded camera
controls. Camera input now lives in one component, navigation::handle,
which the modelling viewport and the Render preview both call (NavCaps:
orbit, pick). Render gets the navigation preset, Orbit around, zoom to the
cursor, the middle double-click and the axis view or navigation cube.
Flat pages can call it with orbit off. A test rejects pages that read the
wheel or move the camera themselves.

Fixes #1454

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

* Render panel hint says the camera moves as in Design

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

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

assets/locales/de.json

@@ -867,7 +867,7 @@
   "render.reload_settings": "Gespeicherte Einstellungen laden",
   "render.unavailable_preview": "Dieses Setup verlangt ein nicht verfügbares Vorschauprofil.",
   "render.use_preview": "Integrierte Vorschau verwenden",
-  "render.navigation_help": "Ziehen zum Drehen; mit mittlerer Taste ziehen zum Verschieben; scrollen zum Zoomen. Setup speichern übernimmt die aktuelle Kamera.",
+  "render.navigation_help": "Die Kamera bewegt sich wie im Konstruieren (Einstellungen › Navigation). Setup speichern übernimmt die aktuelle Kamera.",
   "render.return_design": "Zurück zu Design",
   "render.image_title": "Bild rendern",
   "render.image_help": "CPU-Vorschaubild · PNG · angenäherte Transparenz",