feat(testing): add Anvil fork local testing infrastructure

Complete local testing setup with Anvil fork of Arbitrum mainnet:

Infrastructure:
- Docker Compose orchestration (Anvil, MEV Bot, Prometheus, Grafana)
- Anvil fork configuration with 1-second blocks
- Multi-stage Dockerfile for optimized builds
- Health checks and auto-restart policies

Configuration:
- Comprehensive .env.example with all parameters
- Prometheus metrics collection setup
- Grafana datasource provisioning
- .gitignore to prevent committing secrets

Testing Scripts:
- setup-local-fork.sh: Initialize fork and fund test wallet
- create-test-swap.sh: Generate test swaps for bot detection
- Both scripts include validation and helpful output

Integration Components:
- pkg/sequencer/reader.go: WebSocket reader for pending transactions
  - Worker pool pattern (10 workers)
  - <50ms processing target
  - Front-running capability
  - Auto-reconnection with exponential backoff

- pkg/pools/discovery.go: Pool discovery service
  - UniswapV2-style pools (SushiSwap, Camelot)
  - UniswapV3 pools (multiple fee tiers)
  - Factory contract queries
  - Liquidity filtering

Documentation:
- TESTING.md: Complete testing guide
  - Quick start instructions
  - Testing scenarios
  - Monitoring and debugging
  - Performance benchmarks
  - Troubleshooting guide

This enables safe local testing without deploying to public testnet,
using real Arbitrum mainnet state forked locally with Anvil.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,74 @@
+# Environment files with secrets
+.env
+.env.local
+.env.*.local
+
+# Private keys and wallets
+*.key
+*.keystore
+keystore/
+wallets/
+
+# Build artifacts
+bin/
+build/
+dist/
+*.exe
+*.dll
+*.so
+*.dylib
+
+# Test coverage
+*.out
+coverage.html
+coverage.txt
+
+# IDE files
+.vscode/
+.idea/
+*.swp
+*.swo
+*~
+
+# OS files
+.DS_Store
+Thumbs.db
+
+# Logs
+logs/
+*.log
+
+# Data directories
+data/
+*.db
+*.sqlite
+
+# Docker volumes
+volumes/
+
+# Temporary files
+tmp/
+temp/
+*.tmp
+
+# Dependency directories
+vendor/
+node_modules/
+
+# Compiled binaries
+mev-bot-v2
+mev-bot-v1
+
+# Monitoring data
+prometheus-data/
+grafana-data/
+
+# Backup files
+*.bak
+*.backup
+*~
+
+# Archive files
+*.tar
+*.tar.gz
+*.zip