refactor(tools): consolidate LLM tools from 42 to 38

Merge create_task into create_note (set status='todo' for tasks, omit
for notes), merge delete_task into delete_note, consolidate entity
tools (create/update_person → save_person, create/update_place →
save_place), rename get_note → read_note with clearer descriptions,
move calculate out of rag.py into utility.py, and extract shared
duplicate detection into check_duplicate() helper.

Updates all downstream references in generation_task.py, quick_capture.py,
ToolCallCard.vue, and WorkspaceView.vue.

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

src/fabledassistant/services/generation_task.py

@@ -97,12 +97,10 @@ def _should_think(user_content: str, think_requested: bool) -> bool:
 
 # Human-readable labels for each tool, shown in the status indicator
 _TOOL_LABELS: dict[str, str] = {
-    "create_task": "Creating task",
-    "create_note": "Creating note",
-    "update_note": "Updating note",
-    "delete_note": "Deleting note",
-    "delete_task": "Deleting task",
-    "get_note": "Reading note",
+    "create_note": "Creating note/task",
+    "update_note": "Updating note/task",
+    "delete_note": "Deleting note/task",
+    "read_note": "Reading note",
     "list_notes": "Listing notes",
     "list_tasks": "Searching tasks",
     "search_notes": "Searching notes (semantic)",