Fix ResourceData JSON format to use metadata objects

Problem

The MIDI-CI responder was sending incorrect Get Property Data Reply messages for ResourceData requests. Instead of sending an array of objects with metadata like:

[{"resource":"DeviceInfo"},{"resource":"ChannelList"},{"resource":"JSONSchema"},{"resource":"X-6847"}]

It was sending a simple string array:

["DeviceInfo","ChannelList","JSONSchema"]

Solution

This PR ports the missing CommonRulesPropertyMetadata.toJsonValue() function from the Kotlin ktmidi implementation to C++ and updates the ResourceData response generation to use metadata objects instead of plain strings.

Changes Made

1. Added missing constants to PropertyCommonRules.hpp:

   • PropertyResourceFields struct with field name constants (RESOURCE, CAN_GET, CAN_SET, etc.)
   • PropertySetAccess struct with access level constants (NONE, FULL, PARTIAL)

2. Implemented toJsonValue() method in CommonRulesPropertyMetadata:

   • Ported the conditional field inclusion logic from Kotlin
   • Only includes non-default values to keep JSON compact
   • Handles all metadata fields: resource, canGet, canSet, canSubscribe, requireResId, mediaTypes, encodings, schema, canPaginate

3. Updated create_resource_list_json() in CommonRulesPropertyService:

   • Changed from creating simple string arrays to using metadata objects
   • Uses dynamic casting to handle different metadata types
   • Provides fallback metadata creation for non-CommonRules properties

Technical Details

• The implementation follows the exact same conditional logic as the Kotlin version
• Uses the existing json_ish library consistently with codebase patterns
• Maintains backward compatibility by not changing core metadata structure
• Includes proper error handling for schema parsing

Testing

• Project builds successfully with no compilation errors
• All existing functionality preserved
• ResourceData responses now return proper JSON objects with metadata

Link to Devin run

https://app.devin.ai/sessions/9a977e94459d49d0bd682cf0c87ed22e

Requested by

Atsushi Eno (atsushieno@gmail.com)