sky wheel: element contributor display; sign + house tooltips — TDD

sky_save now re-fetches from PySwiss server-side on save so stored
chart_data always carries enriched element format (contributors/stellia/
parades). New sky/data endpoint serves fresh PySwiss data to the My Sky
applet on load, replacing the stale inline json_script approach.

natus-wheel.js: sign ring slices (data-sign-name) and house ring slices
(data-house) now have click handlers with _activateSign/_activateHouse;
em-dash fallback added for classic elements with empty contributor lists.
Action URLs sky/preview, sky/save, sky/data lose trailing slashes.

Jasmine: T12 sign tooltip, T13 house tooltip, T14 enriched element
contributor display (symbols, Stellium/Parade formations, em-dash fallback).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/apps/dashboard/urls.py

@@ -15,6 +15,7 @@ urlpatterns = [
     path('wallet/save-payment-method', views.save_payment_method, name='save_payment_method'),
     path('kit-bag/', views.kit_bag, name='kit_bag'),
     path('sky/', views.sky_view, name='sky'),
-    path('sky/preview/', views.sky_preview, name='sky_preview'),
-    path('sky/save/', views.sky_save, name='sky_save'),
+    path('sky/preview', views.sky_preview, name='sky_preview'),
+    path('sky/save', views.sky_save, name='sky_save'),
+    path('sky/data', views.sky_natus_data, name='sky_natus_data'),
 ]