Every dependency bump in the housekeeping list was already automerging,
but as a pull request - which meant an email and an open PR for every
bump even when it merged itself. Branch-push automerge makes green bumps
invisible; a failing one still surfaces as a pull request. The new
Matrix i18n workflow gates the i18n/requirements.txt ones with a real
exercise of the translation toolchain.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BhJbmhyUpt4qSrKD9cbJ5A