✨ tests: end-to-end suite scaffold + stream-mode scenario

Add tests/e2e/ structure with shared bash helpers and the first
scenario (stream-mode): spin up real Traefik + Crowdsec via docker
compose, mount the repo as a local plugin, add a ban via cscli, verify
the bouncer blocks the matching X-Forwarded-For, then delete the
decision and verify pass-through.

Adds .github/workflows/e2e.yml with one matrix job per scenario
(stream-mode for now), and Makefile targets `e2e` and `e2e_<scenario>`
for local runs.

Refs #328

tests/e2e/scenarios/stream-mode/docker-compose.yml

@@ -0,0 +1,39 @@
+services:
+  traefik:
+    image: traefik:v3.5.0
+    container_name: e2e-stream-traefik
+    command:
+      - "--log.level=INFO"
+      - "--accesslog"
+      - "--api.insecure=true"
+      - "--providers.file.filename=/etc/traefik/dynamic.yml"
+      - "--providers.file.watch=false"
+      - "--entrypoints.web.address=:80"
+      - "--entryPoints.web.forwardedHeaders.insecure=true"
+      - "--experimental.localplugins.bouncer.modulename=github.com/maxlerebourg/crowdsec-bouncer-traefik-plugin"
+    volumes:
+      - ./traefik-dynamic.yml:/etc/traefik/dynamic.yml:ro
+      - ../../../..:/plugins-local/src/github.com/maxlerebourg/crowdsec-bouncer-traefik-plugin
+    ports:
+      - "8000:80"
+    depends_on:
+      crowdsec:
+        condition: service_healthy
+
+  whoami:
+    image: traefik/whoami
+    container_name: e2e-stream-whoami
+
+  crowdsec:
+    image: crowdsecurity/crowdsec:v1.6.8
+    container_name: crowdsec
+    environment:
+      DISABLE_ONLINE_API: "true"
+      BOUNCER_KEY_TRAEFIK: 40796d93c2958f9e58345514e67740e5
+      CUSTOM_HOSTNAME: crowdsec
+    healthcheck:
+      test: ["CMD", "cscli", "lapi", "status"]
+      interval: 2s
+      timeout: 3s
+      retries: 30
+      start_period: 5s

tests/e2e/scenarios/stream-mode/run.sh

@@ -0,0 +1,57 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+HERE="$(cd "$(dirname "$0")" && pwd)"
+# shellcheck source=../../lib/common.sh
+source "$HERE/../../lib/common.sh"
+
+SCENARIO=stream-mode
+PROJECT="e2e-${SCENARIO}"
+COMPOSE_FILE="$HERE/docker-compose.yml"
+LOG_FILE="/tmp/e2e-${SCENARIO}.log"
+
+cleanup() {
+  local rc=$?
+  if (( rc != 0 )); then
+    dump_diagnostics "$PROJECT" "$COMPOSE_FILE" > "$LOG_FILE" 2>&1 || true
+    echo "Scenario failed. Logs written to $LOG_FILE"
+  fi
+  docker compose -p "$PROJECT" -f "$COMPOSE_FILE" down -v --remove-orphans >/dev/null 2>&1 || true
+  exit $rc
+}
+trap cleanup EXIT
+
+echo "[$SCENARIO] starting stack..."
+docker compose -p "$PROJECT" -f "$COMPOSE_FILE" up -d --wait
+
+echo "[$SCENARIO] waiting for crowdsec readiness..."
+wait_crowdsec_ready
+
+echo "[$SCENARIO] waiting for traefik readiness..."
+wait_for_status http://localhost:8000/foo 200 30
+
+echo "[$SCENARIO] no decision yet -> request allowed"
+assert_status http://localhost:8000/foo 200 -H "X-Forwarded-For: 1.2.3.4"
+
+echo "[$SCENARIO] adding ban decision for 1.2.3.4"
+docker exec crowdsec cscli decisions add --ip 1.2.3.4 --type ban --duration 5m
+
+echo "[$SCENARIO] waiting one stream tick + buffer..."
+sleep 6
+
+echo "[$SCENARIO] banned IP must be blocked (HTTP 403)"
+assert_status http://localhost:8000/foo 403 -H "X-Forwarded-For: 1.2.3.4"
+
+echo "[$SCENARIO] non-banned IP must still pass (HTTP 200)"
+assert_status http://localhost:8000/foo 200 -H "X-Forwarded-For: 5.6.7.8"
+
+echo "[$SCENARIO] deleting ban decision"
+docker exec crowdsec cscli decisions delete --ip 1.2.3.4
+
+echo "[$SCENARIO] waiting one stream tick + buffer..."
+sleep 6
+
+echo "[$SCENARIO] previously banned IP must pass again"
+assert_status http://localhost:8000/foo 200 -H "X-Forwarded-For: 1.2.3.4"
+
+echo "[$SCENARIO] OK"

tests/e2e/scenarios/stream-mode/traefik-dynamic.yml

@@ -0,0 +1,22 @@
+http:
+  routers:
+    whoami:
+      rule: "PathPrefix(`/foo`)"
+      entryPoints: [web]
+      service: whoami
+      middlewares: [bouncer]
+  services:
+    whoami:
+      loadBalancer:
+        servers:
+          - url: "http://whoami:80"
+  middlewares:
+    bouncer:
+      plugin:
+        bouncer:
+          enabled: true
+          crowdsecMode: stream
+          updateIntervalSeconds: 3
+          crowdsecLapiKey: "40796d93c2958f9e58345514e67740e5"
+          forwardedHeadersTrustedIPs:
+            - "172.16.0.0/12"