ocioview: MatrixTransform input parameter persistence

When editing a MatrixTransform in ocioview, you have the option of using a number of matrix constructors (fit, sat, scale, view). These take simplified input parameters and populate the transform's matrix and offset arrays. The problem is that there is currently no persistence for the chosen input method. The constructors work for initial entry, but reloading the transform from the config loses the input parameters.

MatrixTransform supports storage of FormatMetadata, which is primarily used when transforms are created from reading a CLF/CTF file. An element could be added to the transform's metadata to store ocioview data including Matrix parameters. This would also allow use of new transform constructors, such as using [colour-science](https://www.colour-science.org/) data to easily populate matrices with color primary or chromatic adaptation transforms.

Inizia tracciando la modifica di MatrixTransform e il ricaricamento della configurazione in ocioview, quindi esamina come MatrixTransform memorizza FormatMetadata. Definisci la rappresentazione dei metadati per il costruttore selezionato e i suoi parametri e verifica che il salvataggio e il ricaricamento preservino gli input del costruttore senza compromettere i metadati CLF/CTF esistenti.

Scritto dal modello di indicizzazione a partire dal testo della issue.