Add routing, cast API conversion, and filters

Introduce client-side routing and cast API support. Key changes:

- Add react-router-dom dependency and wire BrowserRouter in App.
- Convert App to route-based structure (/, /media/:id, /cast, /cast/:id, /add, /import) with MediaDetailRoute and CastDetailRoute helpers.
- Extend API types for cast items and add convertApiCastToStaff; fetchAllCast now returns Staff[] (mapped via converter).
- Update components to use react-router hooks (useNavigate, useParams, useLocation, Link/NavLink): Header links, DetailView, CastDetailView, AddMediaView, ImporterView and others now navigate via routes.
- Enhance CastView: fetch cast list, loading state, persistent search/sort/filter controls, filtering by occupations/media types and enabled categories, improved pagination and UI controls.
- Update stashapp importer: add configurable blacklist check to skip scenes, increase per_page for queries.

These changes consolidate navigation, improve cast data handling from the API, and add richer filtering and importer controls.

package.json

@@ -24,6 +24,7 @@
     "motion": "^12.38.0",
     "react": "^19.0.0",
     "react-dom": "^19.0.0",
+    "react-router-dom": "^7.14.0",
     "shadcn": "^4.2.0",
     "tailwind-merge": "^3.5.0",
     "tw-animate-css": "^1.4.0",