feat: create v2-prep branch with comprehensive planning

Restructured project for V2 refactor:

**Structure Changes:**
- Moved all V1 code to orig/ folder (preserved with git mv)
- Created docs/planning/ directory
- Added orig/README_V1.md explaining V1 preservation

**Planning Documents:**
- 00_V2_MASTER_PLAN.md: Complete architecture overview
  - Executive summary of critical V1 issues
  - High-level component architecture diagrams
  - 5-phase implementation roadmap
  - Success metrics and risk mitigation

- 07_TASK_BREAKDOWN.md: Atomic task breakdown
  - 99+ hours of detailed tasks
  - Every task < 2 hours (atomic)
  - Clear dependencies and success criteria
  - Organized by implementation phase

**V2 Key Improvements:**
- Per-exchange parsers (factory pattern)
- Multi-layer strict validation
- Multi-index pool cache
- Background validation pipeline
- Comprehensive observability

**Critical Issues Addressed:**
- Zero address tokens (strict validation + cache enrichment)
- Parsing accuracy (protocol-specific parsers)
- No audit trail (background validation channel)
- Inefficient lookups (multi-index cache)
- Stats disconnection (event-driven metrics)

Next Steps:
1. Review planning documents
2. Begin Phase 1: Foundation (P1-001 through P1-010)
3. Implement parsers in Phase 2
4. Build cache system in Phase 3
5. Add validation pipeline in Phase 4
6. Migrate and test in Phase 5

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

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

orig/pkg/scanner/market/pool_validator.go

@@ -0,0 +1,82 @@
+package market
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/ethclient"
+
+	"github.com/fraktal/mev-beta/internal/logger"
+)
+
+// PoolValidator provides pool address validation before RPC queries
+type PoolValidator struct {
+	logger *logger.Logger
+	client *ethclient.Client
+}
+
+// NewPoolValidator creates a new pool validator
+func NewPoolValidator(logger *logger.Logger, client *ethclient.Client) *PoolValidator {
+	return &PoolValidator{
+		logger: logger,
+		client: client,
+	}
+}
+
+// IsValidPoolAddress performs comprehensive validation on a pool address
+// Returns true only if the address is worth querying from RPC
+func (pv *PoolValidator) IsValidPoolAddress(ctx context.Context, addr common.Address) (bool, string) {
+	// Check 1: Address must not be zero
+	if addr == (common.Address{}) {
+		return false, "zero address"
+	}
+
+	// Check 2: Address must be a valid Ethereum address format
+	if !isValidEthereumAddress(addr) {
+		return false, "invalid address format"
+	}
+
+	// Check 3: If we have a client, verify contract exists at this address
+	// This is the primary defense against invalid pool addresses
+	if pv.client != nil {
+		codeSize, err := getContractCodeSize(ctx, pv.client, addr)
+		if err != nil {
+			// Network errors are transient - allow retry
+			pv.logger.Debug(fmt.Sprintf("Transient error checking contract for %s: %v (will retry)", addr.Hex(), err))
+			return true, "" // Allow retry for transient failures
+		}
+
+		// Zero bytecode means definitely no contract
+		if codeSize == 0 {
+			return false, "no contract deployed"
+		}
+
+		// Contract exists - but may still be non-standard, let RPC call handle that
+		return true, ""
+	}
+
+	return true, ""
+}
+
+// getContractCodeSize returns the size of bytecode at an address
+// Size 0 means no contract is deployed
+func getContractCodeSize(ctx context.Context, client *ethclient.Client, addr common.Address) (int, error) {
+	code, err := client.CodeAt(ctx, addr, nil)
+	if err != nil {
+		return -1, err
+	}
+	return len(code), nil
+}
+
+// isValidEthereumAddress validates basic Ethereum address format
+func isValidEthereumAddress(addr common.Address) bool {
+	// Address must not be all zeros or all ones (obviously fake)
+	zeroAddr := common.Address{}
+	if addr == zeroAddr {
+		return false
+	}
+
+	// Check if it's a valid hex address length (already checked by common.Address type)
+	return true
+}

orig/pkg/scanner/market/validation_test.go

@@ -0,0 +1,45 @@
+package market
+
+import (
+	"errors"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/fraktal/mev-beta/internal/config"
+	"github.com/fraktal/mev-beta/internal/logger"
+)
+
+func TestNormalizeAndValidatePoolAddress(t *testing.T) {
+	cfg := &config.BotConfig{
+		MaxWorkers: 1,
+		RPCTimeout: 1,
+	}
+	log := logger.New("info", "text", "")
+	scanner := NewMarketScanner(cfg, log, nil, nil)
+
+	t.Run("accepts known pool", func(t *testing.T) {
+		address := "0xC6962004f452bE9203591991D15f6b388e09E8D0" // known Uniswap V3 pool
+		normalized, result, err := scanner.normalizeAndValidatePoolAddress(address)
+		require.NoError(t, err)
+		require.NotNil(t, result)
+		require.Equal(t, "0xc6962004f452be9203591991d15f6b388e09e8d0", normalized)
+		require.True(t, result.IsValid)
+	})
+
+	t.Run("rejects known token misclassified as pool", func(t *testing.T) {
+		address := "0x82aF49447D8a07e3bd95BD0d56f35241523fBab1" // WETH
+		_, result, err := scanner.normalizeAndValidatePoolAddress(address)
+		require.Error(t, err)
+		require.NotNil(t, result)
+		require.True(t, errors.Is(err, ErrInvalidPoolCandidate))
+	})
+
+	t.Run("rejects corrupted address", func(t *testing.T) {
+		address := "0x0000000000000000000000000000000000000000"
+		_, result, err := scanner.normalizeAndValidatePoolAddress(address)
+		require.Error(t, err)
+		require.NotNil(t, result)
+		require.True(t, errors.Is(err, ErrInvalidPoolCandidate))
+	})
+}