Add CustomFormatter support

[okms]

This pull request introduces support for custom view formatting in list and document views, ensuring that custom formatter objects are properly handled and serialized. The main changes include schema updates, code modifications to normalize custom formatter settings, and integration of these improvements in handlers for lists and files.

Schema enhancements:

• Added the CustomFormatter property to the AdditionalSettings section of the IListView interface and updated schema.json to accept both string and object types for CustomFormatter. [1] [2]

View configuration improvements:

• Updated the sample schema in all-simple.ts to include a Views array with a sample custom formatter configuration for the "All Documents" view.

Normalization utility:

• Introduced the normalizeViewAdditionalSettings function in src/util/index.ts to serialize CustomFormatter objects into strings, ensuring compatibility with SharePoint APIs.

Handler integration:

• Modified the Lists and Files handlers to use normalizeViewAdditionalSettings when updating or adding views, so that custom formatter objects are always serialized before being sent to SharePoint. [1] [2] [3] [4] [5]

[olemp]

Denied!