Add option to scale instance to different tagged service offering

### The required feature described as a wish

As an end-user, I would like to be able to scale an existing instance to a service offering with a different hosttag than the current service offering assigned to the instance. If not unversially allowed by default, an option to allow for this to be enabled would be very helpful.

As it stands today, making this transition requires using an untagged offering as a "shim" to then transition to another offering. This is a bit of a clunky user experience that could easily create confusion for end user.

El issue no identifica archivos, pruebas ni puntos de entrada. Empieza por localizar las rutas de escalado de instancias y de transición entre ofertas de servicio, y después determina cómo se debe autorizar y validar un cambio de oferta etiquetada; se considera terminado cuando una instancia puede pasar directamente entre ofertas con etiquetas diferentes sin usar un shim sin etiquetar.

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