feat: add unified memory routing to consolidation service

- Add MemoryRouteClassification and MemoryRoutingResult models
- Implement unified classifier (_classify_web_results_unified) that routes
  web results to: wiki, volatile, file (Paperless), prefetch, or skip
- Add routing methods: _route_to_volatile, _route_to_files, _register_prefetch
- Update _process_search to use unified classifier instead of separate analysis
- Add get_volatile_cache_service factory to dependencies
- Wire volatile_service and settings_client into ConsolidationService
- Update ConsolidationResult/Response with new routing counters

Test fixes:
- Fix WikiJSClient fixtures to use api_token instead of username/password
- Fix entity linking test assertions to expect full user-namespaced paths
- Add sample_unified_classification fixture for new classifier format

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

tests/conftest.py

@@ -45,8 +45,7 @@ def wikijs_test_config() -> dict:
     settings = get_settings()
     return {
         "base_url": f"http://{TEST_HOST}:3000",
-        "username": settings.wikijs_username,
-        "password": settings.wikijs_password
+        "api_token": settings.wiki_graphql_api
     }