Fix: Error messages were not properly captured in the frontend.

Feature: F5,6,7 to change between Receipt, Payment and Journal voucher.

brewman/pyproject.toml

@@ -36,8 +36,8 @@ build-backend = "poetry.core.masonry.api"
 
 [tool.ruff]
 line-length = 120
-# Assume Python 3.12.
-target-version = "py312"
+# Assume Python 3.13.
+target-version = "py313"
 exclude = [
     ".eggs",
     ".git",