Add ERC-8004 verdict card and detail section #10
Description
Add ERC-8004 / Reputation section to the web UI:
- New verdict card showing on-chain registration status
- Detail section with agent ID, registry, chain, services
- On-chain reputation display (feedback count, avg value, validation count)
- Categories grid for ERC-8004 related flags
Data already available from mcp-agent-assessment Layer 4 + Layer 5.