Deal with non-primitive component value types

[sergei-maertens]

Currently we require type casts for component value types like AddressData and UploadedFileData (and the CustomerProfile) which are valid JSON-serializable interfaces but are not assignable to JSONObject because of the missing string index.

The JSONValue / JSONObject types express that the data is inherently exchanged over the wire as JSON, but this doesn't work 100% with this intent in the TS type system. We also want to more strictly model the component value type where we have more information, so relaxing to wider types breaks DX and IDE autocompletion & removes strong guarantees that we know we have.

Examples of where this is happening:

formio-renderer/src/registry/addressNL/initialValues.ts

Line 27 in 124bf72

return {[key]: defaultValue as unknown as JSONObject};

formio-renderer/src/registry/file/initialValues.ts

Line 11 in 124bf72

return {[key]: [] satisfies JSONObject[]};

formio-renderer/src/registry/partners/initialValues.ts

Line 14 in 124bf72

return {[key]: defaultValue as unknown as JSONValue[]};

formio-renderer/src/registry/editgrid/initialValues.ts

Line 21 in 124bf72

return {[key]: defaultValue as JSONObject[]};

And cases where we discussed this:

• Implement component type: profile #178 (comment)
• Implement addressNL component type #166 (comment)

We can only address this once we don't depend on formio.js SDK at all anymore.