[Bug] audio.pins in keyboard.json is not converted to C defines during build

Bug Description

The audio.pins property defined in keyboard.json is not converted to AUDIO_PIN / AUDIO_PIN_ALT C defines during the build process, even though it is a valid property in the keyboard JSON schema.

Expected Behavior

When audio.pins is specified in keyboard.json, the build system should generate the corresponding AUDIO_PIN and AUDIO_PIN_ALT defines in info_config.h, similar to how other audio.* properties are handled.

Actual Behavior

The audio.pins value is silently ignored during build. Users must still manually define AUDIO_PIN / AUDIO_PIN_ALT in config.h for audio to work.

Details

• The JSON schema (data/schemas/keyboard.jsonschema) defines audio.pins as a valid mcu_pin_array.
• All other audio.* properties have mappings in data/mappings/info_config.hjson and are correctly converted to C defines via generate_config_items() in lib/python/qmk/cli/generate/config_h.py.
• The reverse direction (config.h → keyboard.json) works correctly: _extract_audio() in lib/python/qmk/info.py reads legacy B5_AUDIO, B6_AUDIO, etc. and populates audio.pins.
• However, audio.pins has no entry in info_config.hjson, so the forward direction (keyboard.json → C defines) is missing.

Affected Properties

Property	keyboard.json → C	config.h → keyboard.json
audio.default.on	✅	✅
audio.default.clicky	✅	✅
audio.driver	✅ (rules.mk)	✅
audio.power_control.pin	✅	✅
audio.power_control.on_state	✅	✅
audio.voices	✅	✅
audio.macro_beep	✅	✅
audio.pins	❌ Missing	✅