Resolve "Update documentation"

docs/source/contact.md

docs/source/development/client.md

docs/source/development/external.md

docs/source/development/further.md

docs/source/development/vscode.md

docs/source/documentation/client.md

docs/source/installation/client.md

docs/source/installation/server.md

docs/source/overview/overview.md

docs/source/overview/server.md

docs/source/testing/client.md

docs/source/testing/e2e.md

docs/source/user_manual/editor.md

docs/source/user_manual/presentation.md

server/app/database/__init__.py

server/app/database/controller/delete.py

server/app/database/controller/edit.py

server/app/database/controller/utils.py