✨ feat(ui): show skill name in tool display

GenericTool now shows 'skill: frontend-design' instead of just 'skill'
when a skill tool is called. Also shows metadata name as subtitle.

The thinking/redacted_thinking block error is a known Claude API
constraint where thinking blocks in assistant messages cannot be
modified during compaction. This requires deeper investigation of
MessageV2.toModelMessages serialization. Filed for future fix.

Author: praxstack