[fix] [download] Refactor

.storybook/preview-head.html

CHANGELOG.md

MIGRATION.md

angular.json

.../ngx-dsfr-components/src/lib/commons/i18n/i18n.service.ts

projects/ngx-dsfr-components/src/lib/commons/index.ts

...r-components/src/lib/commons/utils/file-size-unit.type.ts

...s/ngx-dsfr-components/src/lib/commons/utils/file-utils.ts

...-dsfr-components/src/lib/commons/utils/media-type.enum.ts

.../ngx-dsfr-components/src/lib/download/download-variant.ts

...-dsfr-components/src/lib/download/download.component.html

...-dsfr-components/src/lib/download/download.component.scss

...gx-dsfr-components/src/lib/download/download.component.ts

...ects/ngx-dsfr-components/src/lib/download/download.doc.md

...s/ngx-dsfr-components/src/lib/download/download.module.ts

...cts/ngx-dsfr-components/src/lib/download/download.spec.ts

.../ngx-dsfr-components/src/lib/download/download.stories.ts

...ts/ngx-dsfr-components/src/lib/download/dsfr-mime.type.ts

projects/ngx-dsfr-components/src/lib/download/index.ts

...dsfr-components/src/lib/downloads-group/download.model.ts