[verified] Implement account valuation history for issue 12

tests/test_ledger_categories.py

@@ -6,7 +6,7 @@ from jarca_ledger_mcp import service
 def test_ledger_category_create_list_delete_reactivate(tmp_path):
     db_path = str(tmp_path / "ledger.sqlite3")
     health = service.health_check(db_path)
-    assert health["schema_version"] == "11"
+    assert health["schema_version"] == "12"
 
     created = service.create_ledger_category("반려동물", "사료", sort_order=250, memo="test", db_path=db_path)
     assert created["success"] is True