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/server_internal_test.go

@@ -0,0 +1,19 @@
+package rest
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestNewServerUsesEphemeralJWTSecretWhenUnset(t *testing.T) {
+	t.Setenv("JWT_SECRET", "")
+
+	first := NewServer(nil, 138)
+	second := NewServer(nil, 138)
+
+	require.NotEmpty(t, first.jwtSecret)
+	require.NotEmpty(t, second.jwtSecret)
+	require.NotEqual(t, []byte("change-me-in-production-use-strong-random-secret"), first.jwtSecret)
+	require.NotEqual(t, string(first.jwtSecret), string(second.jwtSecret))
+}