refactor: consolidate nfo modules into src/server/nfo/

Move nfo_models, tmdb_client, nfo_generator, nfo_mapper from
scattered temp directories into single src/server/nfo/ package.
Update all imports to reflect new structure.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

tests/api/test_nfo_diagnostics_repair.py

@@ -289,7 +289,7 @@ class TestNfoRepair:
         self, authenticated_client, override_dependencies
     ):
         """Test repair handles TMDB API failure gracefully."""
-        from src.server.services_nfo_temp.tmdb_client import TMDBAPIError
+        from src.server.nfo.tmdb_client import TMDBAPIError
 
         with patch("src.server.api.nfo.Path") as MockPath:
             mock_path = Mock()