fix(integration): migrate wget-style curl syntax for Debian compatibility

After migrating base image from Alpine to Debian Trixie (PR #550),
integration test scripts were using wget-style options with curl
that don't work correctly on Debian.

Changed curl -q -O- (wget syntax) to curl -sf (proper curl):

waf_integration.sh
cerberus_integration.sh
rate_limit_integration.sh
crowdsec_startup_test.sh
install-go-1.25.5.sh
Also added future phase to plan for Playwright security test helpers
to prevent ACL deadlock issues during E2E testing.

Refs: #550

scripts/rate_limit_integration.sh

@@ -166,7 +166,7 @@ docker run -d --name ${CONTAINER_NAME} \
 
 echo "Waiting for Charon API to be ready..."
 for i in {1..30}; do
-    if curl -s -f http://localhost:8280/api/v1/ >/dev/null 2>&1; then
+    if curl -s -f http://localhost:8280/api/v1/health >/dev/null 2>&1; then
         echo "✓ Charon API is ready"
         break
     fi
@@ -187,7 +187,7 @@ docker run -d --name ${BACKEND_CONTAINER} --network containers_default kennethre
 
 echo "Waiting for httpbin backend to be ready..."
 for i in {1..20}; do
-    if docker exec ${CONTAINER_NAME} sh -c "curl -q -O- http://${BACKEND_CONTAINER}/get 2>/dev/null || curl -s http://${BACKEND_CONTAINER}/get" >/dev/null 2>&1; then
+    if docker exec ${CONTAINER_NAME} sh -c "curl -sf http://${BACKEND_CONTAINER}/get" >/dev/null 2>&1; then
         echo "✓ httpbin backend is ready"
         break
     fi