feat(logger): add @pleaseai/logger package with pino integration

Create new logger package for structured logging across the monorepo:
- pino-based implementation for high performance
- Auto-detects pretty printing via NODE_ENV
- Redacts sensitive fields (password, secret, token, apiKey, etc.)
- All output to stderr (stdout reserved for protocol data)
- Typed API: createLogger(name) factory and default logger singleton

Issue: #36

Author: amondnet