feat: explorer API, wallet, CCIP scripts, and config refresh

- Backend REST/gateway/track routes, analytics, Blockscout proxy paths.
- Frontend wallet and liquidity surfaces; MetaMask token list alignment.
- Deployment docs, verification scripts, address inventory updates.

Check: go build ./... under backend/ (pass).
Made-with: Cursor

backend/api/rest/stats_internal_test.go

@@ -0,0 +1,73 @@
+package rest
+
+import (
+	"context"
+	"errors"
+	"strings"
+	"testing"
+
+	"github.com/jackc/pgx/v5"
+	"github.com/stretchr/testify/require"
+)
+
+type fakeStatsRow struct {
+	scan func(dest ...any) error
+}
+
+func (r fakeStatsRow) Scan(dest ...any) error {
+	return r.scan(dest...)
+}
+
+func TestLoadExplorerStatsReturnsValues(t *testing.T) {
+	var call int
+	queryRow := func(_ context.Context, _ string, _ ...any) pgx.Row {
+		call++
+		return fakeStatsRow{
+			scan: func(dest ...any) error {
+				target, ok := dest[0].(*int64)
+				require.True(t, ok)
+
+				switch call {
+				case 1:
+					*target = 11
+				case 2:
+					*target = 22
+				case 3:
+					*target = 33
+				case 4:
+					*target = 44
+				default:
+					t.Fatalf("unexpected query call %d", call)
+				}
+				return nil
+			},
+		}
+	}
+
+	stats, err := loadExplorerStats(context.Background(), 138, queryRow)
+	require.NoError(t, err)
+	require.Equal(t, int64(11), stats.TotalBlocks)
+	require.Equal(t, int64(22), stats.TotalTransactions)
+	require.Equal(t, int64(33), stats.TotalAddresses)
+	require.Equal(t, int64(44), stats.LatestBlock)
+}
+
+func TestLoadExplorerStatsReturnsErrorWhenQueryFails(t *testing.T) {
+	queryRow := func(_ context.Context, query string, _ ...any) pgx.Row {
+		return fakeStatsRow{
+			scan: func(dest ...any) error {
+				if strings.Contains(query, "COUNT(*) FROM transactions") {
+					return errors.New("boom")
+				}
+				target, ok := dest[0].(*int64)
+				require.True(t, ok)
+				*target = 1
+				return nil
+			},
+		}
+	}
+
+	_, err := loadExplorerStats(context.Background(), 138, queryRow)
+	require.Error(t, err)
+	require.Contains(t, err.Error(), "query total transactions")
+}