✅ test(e2e/redis): exercise read-from-replica path

The redis scenario only set redisCacheHost, so it validated the writer
but never the round-robin reader path this feature adds. Split the mock
into two roles: the primary (--redis-addr) now answers every GET with a
miss, while the replica (--redis-read-addr) serves the hardcoded
verdicts. The scenario points redisCacheReadHosts at the replica (twice,
to drive round-robin), so the banned-IP-blocked assertion only passes if
the plugin actually reads decisions from the replica rather than the
primary.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tests/e2e/mock/scenarios/redis/dynamic.yml

@@ -23,5 +23,8 @@ http:
           crowdsecLapiKey: "@@APIKEY@@"
           redisCacheEnabled: "true"
           redisCacheHost: "@@REDIS_HOST@@"
+          redisCacheReadHosts:
+            - "@@REDIS_READ_HOST@@"
+            - "@@REDIS_READ_HOST@@"
           forwardedHeadersTrustedIps:
             - "127.0.0.1/32"