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>

Dockerfile

@@ -0,0 +1,55 @@
+# Multi-stage build for MEV Bot V2
+
+# Stage 1: Build
+FROM golang:1.21-alpine AS builder
+
+# Install build dependencies
+RUN apk add --no-cache git make gcc musl-dev linux-headers
+
+# Set working directory
+WORKDIR /build
+
+# Copy go mod files
+COPY go.mod go.sum ./
+
+# Download dependencies
+RUN go mod download
+
+# Copy source code
+COPY . .
+
+# Build the application
+RUN go build -o mev-bot-v2 -ldflags="-w -s" ./cmd/mev-bot-v2
+
+# Stage 2: Runtime
+FROM alpine:latest
+
+# Install runtime dependencies
+RUN apk add --no-cache ca-certificates tzdata
+
+# Create non-root user
+RUN addgroup -g 1000 mevbot && \
+    adduser -D -u 1000 -G mevbot mevbot
+
+# Set working directory
+WORKDIR /app
+
+# Copy binary from builder
+COPY --from=builder /build/mev-bot-v2 .
+
+# Create directories
+RUN mkdir -p /app/logs /app/data && \
+    chown -R mevbot:mevbot /app
+
+# Switch to non-root user
+USER mevbot
+
+# Expose metrics port
+EXPOSE 9090
+
+# Health check
+HEALTHCHECK --interval=30s --timeout=10s --start-period=5s --retries=3 \
+    CMD wget --no-verbose --tries=1 --spider http://localhost:9090/metrics || exit 1
+
+# Run the application
+ENTRYPOINT ["/app/mev-bot-v2"]