Adds cover generation functionality for week notes, using a background image and specified font.
Updates dependencies to the latest versions, including flake8, certifi, click, identify, platformdirs, pygments, python-dotenv, requests, urllib3, and weeknotebot.
- Modified webmentions JSON data to reorder entries and update URLs.
- Updated `electron-to-chromium` version in `package-lock.json` from 1.5.155 to 1.5.157.
- Added `pillow==11.2.1` to `requirements.txt`.
- Updated multiple character image files in the `static/Characters` directory.
