Merge branch 'main' into dev

backend/Dockerfile

backend/app/crud.py

backend/app/database.py

backend/app/main.py

backend/app/models.py

backend/app/schemas.py

backend/app/utils.py

backend/requirements.txt

frontend/Dockerfile

frontend/package-lock.json

frontend/package.json

frontend/src/lang/fr.json

frontend/src/lib/api/auth.ts

frontend/src/lib/api/users.ts

frontend/src/lib/components/header.svelte

frontend/src/lib/components/sessions/message.svelte

frontend/src/lib/components/sessions/writebox.svelte

frontend/src/lib/components/users/userItem.svelte

frontend/src/lib/components/users/weeklySurvey.svelte

frontend/src/lib/config.ts