feat: Knowledge view + entity types (People, Places, Lists)

Data model:
- Migration 0036: adds note_type TEXT (default 'note') and metadata JSONB
  to the notes table; index on note_type
- Note model: entity_type property, note_type/metadata in to_dict()
- create_note() accepts note_type and metadata params

Backend:
- /api/knowledge — unified paginated endpoint: type/tag/sort/q filters,
  semantic search via embeddings, excludes tasks
- /api/knowledge/tags — distinct tags across knowledge objects
- New LLM tools: create_person, create_place, create_list, add_to_list,
  clear_checked_items — all wired into execute_tool()
- People and places auto-injected as compact summary into LLM system prompt

Frontend:
- KnowledgeView replaces HomeView at /; left filter panel (type+tag),
  toolbar (search, sort, graph toggle), card grid with type-aware cards
  (indigo=note, emerald=person, amber=place, sky=list), load-more pagination
- Today bar: upcoming events, overdue task count, Briefing/Chat links
- Floating mini-chat sticky to bottom: creates/continues a conversation
  inline, message history expands upward, close button ends session
- Graph panel: toggles as a 420px right panel at full viewport width
- AppHeader: Knowledge, Chat, Briefing, Calendar, Tasks, Projects
- Router: / → KnowledgeView; /knowledge redirect; HomeView import removed

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

src/fabledassistant/services/notes.py

@@ -57,6 +57,8 @@ async def create_note(
     priority: str | None = None,
     due_date: date | None = None,
     recurrence_rule: dict | None = None,
+    note_type: str = "note",
+    metadata: dict | None = None,
 ) -> Note:
     # Auto-populate project_id from milestone when not explicitly provided
     if milestone_id is not None and project_id is None:
@@ -82,6 +84,8 @@ async def create_note(
             priority=priority,
             due_date=due_date,
             recurrence_rule=recurrence_rule,
+            note_type=note_type,
+            metadata=metadata,
         )
         session.add(note)
         await session.commit()