v1.31.0

Changed

• Runtime dependency bumps. gunicorn 23 → 26, argon2-cffi
  23 → 25, markdown-it-py 3 → 4, mdit-py-plugins 0.4 → 0.6,
  markdownify 0.13 → 1.2. The full test suite (rendering
  pipeline, importers, auth verification) passes against the new
  versions without behaviour-change surface; argon2-cffi 25 still
  verifies hashes produced by 23.x. Operators with deeply
  customised gunicorn configs should skim the gunicorn 24/25/26
  release notes; the in-tree compose defaults work unchanged.
• Python floor raised to 3.14. requires-python is now
  >=3.14,<4 (was >=3.12,<4). Installs against Python 3.12 and
  3.13 will fail at pip install bragi-cms resolution time. The
  [tool.ruff] target-version and [tool.mypy] python_version are
  bumped in lockstep with the floor, and CI now exercises 3.14
  instead of 3.12. Operators on the published Docker images
  (bragi-admin / bragi-delivery) are unaffected; those have
  always run python:3.14-slim. Direct PyPI installers on the
  older interpreters need to upgrade.