feat: expose tenant wallet and balance in app shell

[aledefra]

Summary

• derive tenant wallet address server-side from configured tenant private key env
• resolve Base RPC URL from env/network defaults and query live wallet ETH balance in /api/config
• extend runtime config payload/types with tenant wallet fields
• display tenant wallet address and balance in app footer
• remove env/config console logging from runtime config module to avoid leaking sensitive data

Validation

• npm install
• npm run typecheck
• npm run lint (passes with existing warning in lib/hooks/useJobs.ts)