feat: add back button on preservation sub menu

...n-policy-list/admin-dissemination-policy-list.routable.ts

...ing-agencies-list/admin-funding-agencies-list.routable.ts

...admin-institution-list/admin-institution-list.routable.ts

...utables/admin-license-list/admin-license-list.routable.ts

...utables/admin-oai-set-list/admin-oai-set-list.routable.ts

...n-oauth2-client-list/admin-oauth2-client-list.routable.ts

...utables/admin-orgunit-list/admin-orgunit-list.routable.ts

...routables/admin-person-list/admin-person-list.routable.ts

...on-policy-list/admin-preservation-policy-list.routable.ts

...nts/routables/admin-role-list/admin-role-list.routable.ts

...sion-policy-list/admin-submission-policy-list.routable.ts

...nts/routables/admin-user-list/admin-user-list.routable.ts

...omponents/routables/deposit-list/deposit-list.routable.ts

...omponents/routables/orgunit-list/orgunit-list.routable.ts

...on/job/components/routables/job-list/job-list.routable.ts

...on/sip/components/routables/sip-list/sip-list.routable.ts

...les/shared-abstract-list/shared-abstract-list.routable.ts

src/assets/i18n/de.json

src/assets/i18n/en.json

src/assets/i18n/fr.json