FEAT #14214 TIME 6 front check install

src/frontend/app/app-routing.module.ts

src/frontend/app/app.component.ts

.../app/installer/install-action/install-action.component.ts

src/frontend/app/installer/installer.component.html

src/frontend/app/installer/installer.component.ts

src/frontend/app/installer/welcome/welcome.component.html

src/frontend/app/installer/welcome/welcome.component.ts

src/frontend/app/login/login.component.html

src/frontend/app/login/login.component.ts

src/frontend/plugins/modal/alert.component.html

src/frontend/service/app-light.guard.ts

src/frontend/service/app.guard.ts

src/frontend/service/app.service.ts

src/frontend/service/auth-interceptor.service.ts

src/frontend/service/auth.service.ts

src/frontend/service/functions.service.ts

src/frontend/service/local-storage.service.ts

src/frontend/service/privileges.service.ts

src/frontend/tslint.json

src/lang/lang-fr.json