Merge branch '425890-add-anthropic-for-code-generation' into 'master'

Add Anthropic support for code generation

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/132735



Merged-by: Jan Provaznik <jprovaznik@gitlab.com>
Approved-by: Jan Provaznik <jprovaznik@gitlab.com>
Approved-by: Mikołaj Wawrzyniak <mwawrzyniak@gitlab.com>
Reviewed-by: Jan Provaznik <jprovaznik@gitlab.com>
Reviewed-by: Mikołaj Wawrzyniak <mwawrzyniak@gitlab.com>
Co-authored-by: Vitali Tatarintev <vtatarintev@gitlab.com>