feat: integrate Paperless documents and volatile cache into Librarian

- Add Paperless document search to HybridRAG pipeline
- Add volatile cache (weather, forecast, news, stocks) to HybridRAG
- Add include_documents and include_volatile params to hybrid_search
- Add 📑 and ⚡ icons for document/volatile sources
- Update Librarian prompt with new data source awareness
- Fix Biographer routing: personal memory queries now route correctly
- Add location keywords to Steward pre-fetch logic

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

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

src/agents/librarian/agent.py

@@ -39,7 +39,14 @@ Your role is to help users find, understand, synthesize, and manage information
 - The personal wiki (Wiki.js) containing documentation and notes
 - The knowledge graph (Neo4j) with entities and relationships
 - Vector embeddings (Qdrant) for semantic search
-- Web search (SearXNG) for current information
+- Paperless documents (📑) - indexed PDFs, scanned documents, invoices, receipts from the user's document archive
+- Volatile cache (⚡) - pre-fetched real-time data for user-relevant locations and items:
+  - weather/forecast: conditions and forecasts for user's configured cities
+  - news: headlines from user's preferred sources
+  - stock/crypto: quotes for user's watched symbols
+  - sun/air_quality: data for user's locations
+  - Note: volatile data may not exist for arbitrary queries - falls back to web search
+- Web search (SearXNG) for current information not available in cache
 
 ## Your Personality
 - Scholarly and thorough in your research
@@ -60,7 +67,13 @@ Your role is to help users find, understand, synthesize, and manage information
   - Use for: comparing multiple sources, gathering info from several pages
 
 ### Internal Research Tools
-- **hybrid_search**: Your primary research tool - searches wiki, graph, and web at once
+- **hybrid_search**: Your primary research tool - searches ALL sources at once:
+  - Wiki pages (vector similarity)
+  - Knowledge graph (entity relationships)
+  - Paperless documents (📑 indexed PDFs, scans)
+  - Volatile cache (⚡ weather, news, stocks - when available)
+  - Web search (current information)
+  Results are fused and re-ranked by relevance. Volatile data gets priority when fresh.
 - **search_wiki**: Find specific wiki pages by keyword
 - **semantic_search**: Find conceptually similar content
 - **explore_knowledge_graph** / **find_related_entities**: Discover connections