Fix TestFullDIFCConfigFromJSON timeout waiting for backend connections

The test waited 5s for 'Starting MCPG' in stderr, but that message only
prints after NewUnified() returns. NewUnified blocks on registerAllTools()
which tries to connect backends (Docker container launch has a 30s
timeout). The test's assertions only need DIFC guard registration output.

Fix: wait for '[DIFC] Registered guard' instead, which appears before
the blocking backend connections. Remove the health check (requires full
startup) and the now-unused encoding/json import.

Co-authored-by: Copilot <[email protected]>

Author: lpcox

test/integration/difc_config_test.go

@@ -3,7 +3,6 @@ package integration
 import (
 	"bytes"
 	"context"
-	"encoding/json"
 	"fmt"
 	"net"
 	"net/http"
@@ -412,19 +411,15 @@ func TestFullDIFCConfigFromJSON(t *testing.T) {
 	err := cmd.Start()
 	require.NoError(t, err, "Failed to start gateway")
 
-	ok := waitForStderr(&stderr, "Starting MCPG", 5*time.Second)
-	require.Truef(t, ok, "timeout waiting for gateway stderr to contain %q within %s; stderr:\n%s", "Starting MCPG", 5*time.Second, stderr.String())
-
-	// Try health check
-	resp, err := http.Get(fmt.Sprintf("http://127.0.0.1:%d/health", port))
-	if err == nil {
-		defer resp.Body.Close()
-		assert.Equal(t, http.StatusOK, resp.StatusCode)
+	// Wait for guard registration (appears before the blocking registerAllTools
+	// backend connections that may take 30+ seconds for Docker containers).
+	// "Starting MCPG" only prints after NewUnified returns, which blocks on
+	// backend connections — too slow for this test's DIFC-config-only assertions.
+	ok := waitForStderr(&stderr, "[DIFC] Registered guard", 5*time.Second)
+	require.Truef(t, ok, "timeout waiting for DIFC guard registration within %s; stderr:\n%s", 5*time.Second, stderr.String())
 
-		var health map[string]interface{}
-		json.NewDecoder(resp.Body).Decode(&health)
-		t.Logf("Health response: %+v", health)
-	}
+	// Brief pause to let remaining sequential guard registrations flush to stderr
+	time.Sleep(300 * time.Millisecond)
 
 	cmd.Process.Kill()
 	cmd.Wait()