New "Test senden" button next to Speichern posts current form
credentials (not DB) to /actions/notifications/test, which fires a
test message and redirects back with a flash chip showing the outcome
(including the Telegram API's error description on failure).
telegram_send is now public and returns (ok, detail) so the UI can
surface real error messages ("chat not found", "Unauthorized", etc.).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Container names, FastAPI titles, email subjects, filenames, brand text,
session cookie, User-Agent, docstrings, README. Volume lazyflat_data and
/data/lazyflat.sqlite already used the new name, so on-disk data is
preserved; dropped the now-obsolete legacy-rename comments.
Side effect: SESSION_COOKIE_NAME change logs everyone out on deploy.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>